2nd Meeting on Molecular Simulations · Molecular, este Comité ha tomado la decisión de otorgar...
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2nd Meeting on Molecular Simulations From Simple Fluids to Chemical Reactions and Interactive Molecular Simulation Courses http://quimica.izt.uam.mx/ssm December 9-11, 2010. Location: Building A, Universidad Autónoma Metropolitana. México, D. F.
Transcript of 2nd Meeting on Molecular Simulations · Molecular, este Comité ha tomado la decisión de otorgar...
2nd Meeting on Molecular Simulations
From Simple Fluids to Chemical Reactions
and
Interactive Molecular Simulation Courses
http://quimica.izt.uam.mx/ssm
December 9-11, 2010.
Location:
Building A, Universidad Autónoma Metropolitana. México, D. F.
The Prize of the 2nd Meeting on Molecular
Simulations was awarded to:
DR. GUSTAVO ADOLFO
CHAPELA CASTAÑARES
from Department of Physics at Universidad Autónoma Metropolitana-
Iztapalapa
Message from the Selection Committee to the Organizing Committee Date: Sat, 27 Nov 2010 09:11:15 -0600 Download Re: premio del Simposio de Sim Molec.msg
From: Ana Laura Benavides <[email protected]> Import addresses
[email protected] Block email [email protected] Block SMTP
relay mail-yx0-f172.google.com
To: Alejandre Jose <[email protected]>
Subject: Re: premio del Simposio de Sim Molec All headers
Estimados Dr. Alejandre y Dr. López-Rendón:
Por este medio les informamos que después de analizar las propuestas
que recibimos para el premio del Segundo Simposio de Simulación
Molecular, este Comité ha tomado la decisión de otorgar el premio al
Dr. Gustavo Adolfo Chapela Castañares.
ATENTAMENTE
Dr. Magdaleno Medina
Dra. Ana Laura Benavides
PREFACE
A wide range of complex problems in chemistry, physics,
biology and engineering can be studied and understood at
the molecular level thanks to the explosive growth of
powerful supercomputers and simulation methods. The
knowledge of thermodynamics, dynamics and structural
properties of systems at molecular level allows the design
of better strategies to solve problems in those fields.
The aim of this meeting is to promote the field of
molecular simulations between the Mexican community
and learn about the state of the art of methods and their
applications. This time the speakers come from México,
Europe and United States. The conferences will cover
subjects from simple fluids to chemical reactions.
Introductory courses on Intermolecular Forces, Monte
Carlo and Molecular Dynamics methods will be given the
first day of the meeting.
Applications go from efficient sampling methods, parallel
Molecular dynamics, hydrocarbons, liquid crystals,
colloids, surfactants, water in different environments and
proteins in solution. A Poster session is also programmed.
Participants to the meeting include undergraduate and
graduate students as well as researchers from different
universities.
El Premio del Simposio de Simulación Molecular will be
awarded to an outstanding Mexican scientist.
INFORMACIÓN SOBRE LOS CURSOS DE SIMULACIÓN MOLECULAR
El objetivo de los cursos es presentar los aspectos básicos de los métodos de Simulación
Molecular. Se harán ejercicios computacionales de sistemas sencillos para obtener
potenciales de interacción, propiedades termodinámicas, dinámicas y estructurales a
partir de información molecular. Las aplicaciones sobre temas actuales de investigación
se discutirán en el Simposio.
Es deseable que los interesados tengan conocimientos elementales sobre mecánica
cuántica, termodinámica clásica y mecánica estadística, sin embargo no es requisito
para inscribirse. Los ejercicios están diseñados de tal forma que no se requieren
conocimientos especializados ni de computación ni de simulación molecular.
Los cursos están dirigidos a estudiantes de licenciatura y posgrado de las carreras de
Química, Física, diversas Ingenierías y biología. También a investigadores que desean
incursionar o ampliar sus conocimientos en el campo de la Simulación Molecular.
En el salón habrá un cañón e internet inalámbrico.
Solicitamos a los estudiantes que traigan su laptop, de lo contrario indicarlo al momento
de inscribirse.
INSTRUCCIONES PARA TOMAR LOS CURSOS
Para hacer los ejercicios de los tres cursos, los estudiantes se conectarán desde su laptop
a un cluster de computadoras de la UAM-Iztapalapa. El sistema operativo del cluster es
LINUX. Los estudiantes con laptops con WINDOWS deberán instalar el programa
Cigwin.exe. Este programa así como un manual para su instalación se encuentran en la
página del Simposio (www.quimica.uam.izt.mx/ssm). El tiempo de instalación depende
de la laptop y podría durar hasta UNA HORA. Se le solicita a los estudiantes que
instalen este programa antes de asistir a los cursos. Es muy importante realizar esta
actividad debido a que durante los cursos no dispondremos de tiempo para instalar este
programa. La conexión al cluster permitirá realizar con éxito los ejercicios programados
en los tres cursos.
A los alumnos registrados se les proporcionará información escrita sobre las ecuaciones
básicas de los temas relevantes del curso así como un breve instructivo sobre los
ejercicios que se van a desarrollar en clase.
INTERACTIVE MOLECULAR SIMULATION COURSES
Jueves 9 de Diciembre.
I.- CURSO DE INTERACCIONES MOLECULARES
Instructor: Roberto López-Rendón. UAE-México
Objetivos:
Describir los principales potenciales de interacción que se usan en simulación molecular
con especial énfasis en modelos que se aplican en fluidos simples tales como argón,
agua, hidrocarburos y hasta proteínas en solución.
Programa del curso:
Diferencia entre potencial y fuerza de interacción
Interacciones moleculares y mecánica cuántica
Campo de fuerzas en simulaciones atomísticas.
Interacciones intramoleculares: vibración de distancias y ángulos de enlace y barreras
rotacionales.
Potenciales de corto alcance: esfera dura, pozo cuadrado, Lennard-Jones, Yukawa
Interacciones electrostáticas y sumas de Ewald
Uso del programa Gaussian para obtener:
Geometrías moleculares del agua e hidrocarburos (distancias, ángulos de enlace y
barreras rotacionales)
Cargas atómicas en una molécula
Constante del resorte y distancias de enlace en el agua
Bibliografía:
H. Gould and J. Tobochnik. An Introduction to Computer Simulation Methods:
Applications to Physical Systems. Part 1 and 2 Addison-Wesley, Reading, MA, 1988
A Guide to Simulation. P. Bratley, B. L. Fox, and L. E. Schrage.. Springer-Verlag, New
York
II.- CURSO DE MONTE CARLO
Instructor: Héctor Domínguez, IIM-UNAM
Objetivos:
Entender el funcionamiento de una simulación molecular usando la metodología de
Monte Carlo. Condiciones para usar simulaciones de Monte Carlo, ventajas y
desventajas sobre Dinámica molecular y cuando usar los diferentes ensambles.
Programa del curso (1.5 hr)
1- Introducción al método de Monte Carlo.
Condiciones periódicas, radio de corte y condición de imagen mínima
2.- Ensambles, probabilidad y valores promedio
i) Canónico
ii) Isotérmico-Isobárico
iii) Gran Canónico
Aplicaciones (1.5 hr)
Estudio de un Sistema de Lennard Jones.
- Cambio de un ensamble canónico a un ensamble isotérmico isobárico.
- Cálculo de propiedades termodinámicas en el ensamble canánico e isotérmico
isobárico
Bibliografía
- Computer Simulation of Liquids de MP Allen y DJ Tildesley. Oxford University.
- Understanding Molecular Simulations de D. Frenkel and B. Smit. Computational
Science Series.
III.- CUROS DE DINÁMICA MOLECULAR
Instructor: José Alejandre, UAM-Iztapalapa
Programa:
Trayectoria de átomos y moleculas en función del tiempo.
Algoritmo de Verlet
Operadores de Liouville y algoritmo de Verlet con velocidades
Control de temperatura y presión
Equilibrio y promedios temporales de propiedades físicas
Dinámica Molecular en paralelo
Ejercicios
Simulación de un líquido y un sólido con el potencial de Lennard-Jones
Separación de fases y el equilibrio líquido-vapor
Simulación de hidrocarburos, agua y electrolitos.
Bibliografía:
A. Leach, ―Molecular Modelling: Principles and Applications‖ , 2a. ed. 2001.
MP Allen y DJ Tildesley, Computer Simulations of Liquids, Oxford University Press,
2002.
B. Smit, D. Frenkel, Understanding molecular simulations, Academic Press,
2001
SECOND MEETING ON MOLECULAR SIMULATIONS
10th and 11th of December, 2010.
Building A, Sala del Consejo Académico, UAM-Iztapalapa
PROGRAM
Friday 10th Dic.
8:30-9:00 Open Ceremony
CHAIRMAN: Gustavo Chapela
9:00-9:45 Mark Tuckerman New York University
Enhancing conformational sampling in molecular dynamics simulations.
9:45-10:30: Hector Domínguez IIM-UNAM
Computer simulations of the liquid-liquid and liquid-vapor
coexistence curves for the Perfluorohexane + n-Heptane system
10:30-11:00 COFFEE
11:00-11:45 Margarida Telo da Gama Universidad de Lisboa, Portugal
The ordering transition of self-assembled rigid rods on the square lattice
11:45-12:15 José Luis Rivera IIM-UNAM-Morelia
Frictional Forces in Mixed Hydrophobic-Hydrophilic Alkylsilane
Monolayers on NEMS
12:15-12:30 COFFEE
CHAIRMAN: Pedro Orea
12:30-13:15 Enrique Díaz UAM-Iztapalapa
Molecular dynamics study of stable thermotropic liquid crystalline phases
of disc shaped molecules.
13:15-13:45 Jacqueline Quintana IQ-UNAM
Liquid crystalline phases of two dimensional chiral models.
13:45-15:30 LUNCH
CHAIRMAN: Ana Laura Benavides
15:30-16:00 Pedro Leyva UAM-Iztapalapa
Rotational Microrheology applied to Complex Fluid Systems
16:00-16-15 COFFEE
16:15-17:00 Steve Plimpton Sandia National Labs
Molecular Dynamics Modeling at the Mesoscale
17:00-17:30 Porfirio Luis-Jiménez UAE-México
Clathrate hydrates: applied to hydrogen storage.
17:30-19:30 POSTERS
20:00-23:00 DINNER
Saturday 11th
CHAIRMAN: Minerva González-Melchor
10:00-10:45 Alejandro Gil U. de Guanajuato
Molecular Thermodynamics of Biofuels
10:45-11:30 Iván Ortega ICF-UNAM
The molecular physical chemistry of the transmembrane transport of
toxic metalloids
11:30-12:00 COFFEE
12:00-12:45 Mark Tuckerman New York University
OH-(aq): An ab initio molecular dynamics tale.
12:45-13:15 Noé Mendoza ICF-UNAM
Electrostatic interactions in molecular simulations
13:15-13:30 COFFEE
CHAIRMAN: Jorge López-Lemus
13:30-14:15 Fernando Bresme Imperial College-London
Heat Transfer in Nanoscale Interfaces
14:15-14:45 Nina Pastor UAE-Morelos
Agents that perturb protein folding and promote aggregation of an Ig
Domain
14:45-16:45 LUNCH
CONFERENCES
Enhancing conformational sampling in molecular dynamics
simulations
Mark Tuckerman
Dept. of Chemistry and Courant Institute of Mathematical
Sciences
New York University
100 Washington Square East
New York, NY 10003
One of the computational grand challenge problems is to develop
methodology capable of sampling conformational equilibria in
systems with rough energy landscapes. If met, many important
problems, most notably protein structure prediction, could be
significantly impacted. In this lecture, I will present a series of
techniques for using molecular dynamics to sample such
conformational equilibria. I will begin with simple schemes that
exploit the arbitrariness of the choice of atomic masses in
simulations aimed at predicting static properties to enhance the
efficiency of conformational sampling. I will then describe
reaction coordinate based schemes including adiabatic free energy
dynamics and metadynamics, and finally, I will conclude with a
novel approach in which molecular dynamics is combined with a
novel variable transformation designed to warp configuration
space in such a way that barriers are reduced and attractive basins
stretched. The latter will be compared with replica-exchange
Monte Carlo on a variety of complex systems.
Computer simulations of the liquid-liquid and liquid-vapor
coexistence curves for the Perfluorohexane + n-Heptane
system
Héctor Domínguez
Instituto de Investigaciones en Materiales,
Dept. Reologia y Mecánica de Materiales.
Universidad Nacional Autónoma de México, UNAM
Circuito Exterior, Ciudad Universitaria, Coyoacán, 04510,
México, D. F.
Studies for the interfacial tension of the n-heptane + perfluoro-
nhexane system were carried out at different temperatures and
compositions at vapour-liquid and liquid-liquid interfaces by
using Molecular Dynamics techniques. The vapour-liquid
interfacial tensions were investigated and we observed aneotropy,
i.e. a horizontal inflection at a critical composition as observed by
experiments. On the other hand, for the first time in simulation
work, the test-area method was used for the calculation of liquid-
liquid interfacial tensions. In addition to the interfacial tensions,
studies of the fluid phase equilibria (liquid-liquid (LLE) and
vapour-liquid (VLE)) were also carried out and results were
compared with phase diagrams calculated using an equation of
state (SAFT-VR), and with experimental data when possible;
good agreement was observed.
The ordering transition of self-assembled rigid rods on the
square lattice
Margarida Telo da Gama
Centro de Física Teórica e Computacional
Complexo Interdisciplinar da Universidade de Lisboa
Av. Prof. Gama Pinto, 2
P-1649-003 Lisboa, Portugal
We address the influence of directional interactions, or bonding
sites, on the structure and phase diagram of complex fluids. Using
a generalization of the theory of associating fluids we investigate
the interplay between the self-assembly process, driven by the
bonding interactions, and the ordering transition, driven by the
anisotropic shape of the bonded cluster for a model consisting of
particles with two bonding sites, on a square lattice. The theory is
applied over a wide range of temperature and density and the
results are compared with Monte Carlo simulations. It is shown
that the average length of the equilibrium polydisperse self-
assembled 'rods' is described quantitatively, in both phases. The
ordering transition, which is found to be continuous, is predicted
semi-quantitatively at intermediate densities. Finally, the response
functions are computed and shown to exhibit pronounced
structure at the onset of self-assembly and at the thermodynamic
transition. Extensive Monte Carlo simulations were carried out to
investigate the nature of the ordering transition that is found to be
in the two dimensional Ising universality class, as in models
where the rods are monodisperse. This finding is in contrast with
a recent claim that equilibrium polydispersity changes the nature
of the phase transition in this class of models.
Frictional Forces in Mixed Hydrophobic–Hydrophilic
Alkylsilane Monolayers on NEMS
José Luis Rivera
Instituto de Investigaciones en Materiales
Universidad Nacional Autónoma de México, Apartado Postal 70-
360, 04510 México DF,
México
Hydrophobic (CH3-terminated) and hydrophilic (OH-terminated)
surfaces have been studied and the effects of hydrogen bonds,
chain length, ensemble, and humidity on the frictional properties
determined. Hydrophilic chains show larger adhesion zones than
hydrophobic chains, which are characterized by negative values in
the normal load. The pronounced adhesion of hydrophilic chains
is the result of interfacial hydrogen bonds, which are stronger
than the interfacial forces present in hydrophobic chains. The use
of constant separation vs. constant load ensembles produces
different results in the shear stress; the constant load ensemble
allows the formation of stronger hydrogen bond networks. The
hydrogen bonds also affect the frictional behavior producing
interfacial forces one order of magnitude higher than the
interfacial forces between hydrophobic chains at the characteristic
point of zero-load. The friction forces of mixed hydrophobic and
hydrophilic monolayers with equal length produces intermediate
shear stress values between the behaviors of the pure chains, and
the magnitude of the shear stress depends on the content of
hydrophilic chains. For unequal chain lengths at high loads, there
is a maximum in the magnitude of the shear stress as a function of
the size of the hydrophobic chain length, which creates a buffer
zone between the hydrophilic chains, and produces strong
hydrogen bonding interactions. The presence of interfacial water
molecules between the coats with pure hydrophilic chains, reduce
the magnitude of the shear stress as the water molecules associate
with the hydroxyl groups and block the formation of hydrogen
bonds with other hydroxyl groups.
Molecular dynamics study of stable thermotropic liquid
crystalline phases of disc shaped molecules
Enrique Díaz Herrera
Departamento de Física
Universidad Autónoma Metropolitana-Iztapalapa
Av. San Rafael Atlixco 186, Col. Vicentina
09340 México D.F.
Using molecular dynamics simulations, we discuss the
thermodynamic behavior of a molecular model presenting stable
phases of discotic liquid crystals. Our greater emphasis in this talk
is in the thermodynamic and mainly structural behavior of these
molecular systems which have a potential application in the
design of biosensors and photovoltaic cells. The most stable
phases present in discotic liquid crystals are, the columnar and the
nematic. The columnar phase has long-range translational
periodicity in two dimensions and liquid-like disorder in the third,
whereas the nematic phase is an orientationally ordered
arrangement of discs without any long-range translational order.
This talk describes the detailed structures of the various discotic
phases and some of their important physical properties.
Liquid crystalline phases of two dimensional chiral models
Jacqueline Quintana and Julio Cesar Armas Pérez
Instituto de Química
Universidad Nacional Autónoma de México
Circuito Exterior, Ciudad Universitaria, Delegación Coyoacán
C.P. 04510, México, D.F.
Isotropic-nematic and nematic-smectic transitions are studied for
two infinitely hard models in two dimensions via Monte Carlo
simulations. Nematic order parameter, parallel and perpendicular
correlation functions are computed. System size analysis is
performed to obtain the Frank constant and numerical evidence
indicates that the isotropic-nematic transition is of the Kosterlitz-
Thouless type. Constant pressure and constant volume are used
depending of the property.
Rotational Microrheology applied to Complex Fluid Systems
Pedro Leyva
Depto de Física, Universidad Autónoma Metropolitana-Iztapalapa
Av. San Rafael Atlixco 186, Col. Vicentina, 09340 México D.F.
During last 15 years the microrheological techniques based on the
Brownian Motion of Colloidal Tracers have been used to explore
complex materials beyond the limitations imposed by Mechanical
Bulk Rheology techniques. These microrheological techniques
used among the world by several groups have been mainly based
on the translational motion of colloidal tracers. In this work we
focus our attention both in the translational motion and the
rotational one. We try to explore how the observed mechanical
properties such as viscosity and elasticity are affected depending
on the studied dynamics.
Molecular Dynamics Modeling at the Mesoscale
Steve Plimpton
Scalable Algorithms Dept
Sandia National Laboratories
Albuquerque, NM 87185-1316
Modeling nanoparticle or colloidal systems in a molecular
dynamics code requires coarse-graining on several levels to
achieve meaningful simulation times for study of rheological and
other manufacturing properties. These include treating colloids as
single particles, moving from explicit to implicit solvent, and
capturing hydrodynamic effects. These changes also impact
parallel algorithms for tasks such as finding neighbor particles
and interprocessor communication. I'll describe efficient
techniques we've developed in our LAMMPS molecular
dynnamics code for such models. The first is nanoparticles in a
Lennard-Jones solvent, which involves multiple length scales.
The second is the stochastic rotation dynamics (SRD) formalism,
where solvent particles interact with nanoparticles via collisions
but not with each other. Together these algorithms enable speed-
ups of several orders of magnitude, making solvated nanoparticle
systems more accessible to modeling. I'll highlight the kinds of
system sizes and properties we can now model.
Clathrate hydrates: applied to hydrogen storage.
Daniel Porfirio Luis Jiménez and Jorge López-Lemus
Universidad Autónoma del Estado de México.
Instituto Literario 100, C.P. 50000, Toluca
Since the discovery of clathrate hydrate of hydrogen in 2002,
many efforts have been done to study this compound in many
areas. In the present work we show some recent discoveries made
with molecular simulations in order to observe the capability of
clathrate hydrates to storage hydrogen molecules, after that, the
stability of hydrogen clathrate hydrate was investigated using a
classical molecular dynamics calculation package ―Gromacs‖,
arranging only one hydrogen molecule into each host-frame of the
hydrogen clathrate. Coordination number was evaluated to be
used like stability criteria of the clathrate structure. The diffusion
coefficient of the hydrogen molecules was calculated to observe
how the movement of the H2 molecules can affect the stability of
the structure, and also, an external electric field was applied in the
system to observe how this external perturbation can destabilizing
or stabilizing the hydrate structure. These calculations were done
with a NPT ensemble at a temperature of 100 K and a pressure of
2.5 kbar. SPC/E potential was used for water molecules and a
potential that consists in three sites of partial charges and a
Lennard-Jones site for the molecules of hydrogen.
Molecular Thermodynamics of Biofuels
Felipe Perdomo & Alejandro Gil-Villegas
Departamento de Ingeniería Física
División de Ciencias e Ingenierías
Campus León de la Universidad de Guanajuato
Lomas del Bosque 103, Lomas del campestre
León 37150, Guanajuato México
Biodiesel fuel is a biodegradable clean energetic resource
comprised by a mixture of monoalkyl esters of long chain fatty
acids. In terms of biodegradability and greenhouse-gases effects,
biodiesel fuel is better than diesel fuel. In this talk we present
recent advances in the modeling of biofuel compounds, based on
a molecular-based theory that models the biofuel composed by
three alkylesters: Methyl Oleate, Methyl Palmitate and Methyl
Linolenate. Reactive liquid-vapor equilibria is determined for the
esterification of fatty acid in the presence of acid catalyst to
produce the required biofuel. Thermophysical properties,
including the speed of sound, are predicted, and results are
compared with experimental results.
The molecular physical chemistry of the transmembrane
transport of toxic metalloids
Iván Ortega Blake
Instituto de Ciencias Físicas UNAM.
Arsenic is a very toxic contaminant and highly available in the
biosphere, contaminated water being the main source of arsenic
intake, which is then transported through the cellular membrane.
At first sight it seems surprising that a toxic trivalent ion is
transported through the cell membrane via specific ion channels
since membranes regulate very finely the transport of ions.. A
theoretical study of the hydration of arsenious acid (the most toxic
form of As in solution) is presented. This study included ab initio
calculations and Monte Carlo simulations. The model potentials
used for the simulations were ab initio derived and they include
polarizability, nonadditivity, and molecular relaxation. It is shown
that with these refined potentials it is possible to reproduce the
available experimental evidence and therefore permit the study of
clusters, as well as of the hydration process in solution. From the
study of stepwise hydration and the Monte Carlo simulation of the
condensed phase it is concluded that As(OH)3 presents a
hydration scheme similar to an amphipathic molecule. This
phenomenon is explained as due to the existence of both, a
positive electrostatic potential and a localized lone pair in the
vicinity of As. These results are used to rationalize the known
passage of As OH 3 through aqua-glyceroporines channels that
transport glycerol and urea through the cell membrane in a
selective manner with respect to water. It is possible that similar
hydration patterns for other metalloids could explain their uptake
through the biological membrane
OH-(aq): An ab initio molecular dynamics tale.
Mark Tuckerman
Dept. of Chemistry and Courant Institute of Mathematical
Sciences
New York University
100 Washington Square East
New York, NY 10003
The hydrated hydroxide ion has received considerable attention
recently from both the theoretical and experimental communities
because of its unexpected solvation structures and structural
diffusion mechanism, which stand in sharp contrast to those of the
hydrated excess proton. In this talk, I will review the bulk
hydrogen-bonding patterns and transport mechanism of hydroxide
ion as predicted by ab initio molecular dynamics and ab initio
path integrals and compare the picture suggested by these
calculations to that of the hydrated proton. Experimental evidence
supporting this picture will be briefly reviewed, and very recent
results for the liquid/vapor interface of basic solutions and OH-
reorientation as a function of temperature will be presented.
Electrostatic interactions in molecular simulations
Noé Mendoza.
Instituto de Ciencias Físicas, UNAM
The treatment of electrostatic interactions in molecular
simulations is a very important topic in the study of interfaces. In
the last decade many people have worked to improve the
methodology and the techniques to obatin better results in this
field. One of the most popular and accurate methodologies to
determine the electrostatic interactions in computer simulations is
the Ewald sums. This method is used in many molecular
simulation programs and we can obtain good agreement in results
when compared with experiments. The problem is that this
methodology is computationally expensive. The Wolf method is a
new idea to treat the electrostatic interactions. This method is very
interesting because give us the opportunity to calculate the long
ranged interactions using short ranged forces and in this way
avoid the expensive Fourier calculation. In this talk we discuss
results for water and ionic liquids using the Ewald and Wolf
methods. It shown that the faster Wolf method fails to describe
properly the electrostatic interactions at the liquid-vapor interface.
Other topic that we discuss is the implementation of the point
polarization dipole PPD in our code of molecular dynamics using
the Smooth Particle Mesh Ewald method to speed up the
calculations of the reciprocal contribution. We finally show some
results for ionic salts in the solid phase using polarizable force
fields reported in the literature. The preliminary calculations
show that these force fields do not give the correct properties of
pure components at ambient conditions.
Heat Transfer in Nanoscale Interfaces
Fernando Bresme
Chemical Physics Section, Department of Chemistry,
Imperial College London,
London, UK
Temperature gradients can result in important non equilibrium
processes with practical applications in energy conversion
devices. Recent work on metal nanoparticles and biological
motors suggests the possibility of generating very large thermal
gradients at the nanoscale. Given the small length scale of these
systems the heat transfer process across the interfaces becomes
very important. Computer simulations are particularly useful to
quantify the resistivity of the interfaces as well as the response of
the surrounding fluid to the temperature gradient. In this talk I
will discuss our recent work on non equilibrium molecular
dynamics simulations of aqueous solutions under temperature
gradient. We have found that the water molecules adopt a
preferred orientation as a response to strong temperature
gradients, resulting in significant electrostatic fields. Using
computer simulations of thermal transport in models of
nanoparticles and proteins we will also show that the high
curvature associated to these nanometer size interfaces has a
strong impact on the interfacial resistivity, which is much lower
than in a planar interface.
Agents that perturb protein folding and promote aggregation
of an Ig domain
Carmen Nina Pastor Colón
Facultad de Ciencias, UAE-México
Av. Universidad 1001 Col. Chamilpa
62209 Cuernavaca, Morelos
On their way from the denatured ensemble to the native state,
proteins can get trapped in aggregation prone states. Amyloid
fibers are a type of ordered aggregate that is found in intra and
extracellular deposits in patients suffering from degenerative
diseases such as Alzheimer's, mad cow disease and many other
misfolding diseases. In this work we perturb the native state of an
Ig domain with mutations, low pH and temperature, and explore
the consequences in multiple MD simulations with explicit
solvent. We attempt a description of the conformational landscape
of this protein, prevalent in light chain amyloidosis, with the
intention of identifying plausible folding intermediates that could
serve as seeds for the formation of amyloid fibers.
POSTERS
P1.- El Método de la Matriz Estocástica y su implementación en la modelación de
películas delgadas de óxidos metálicos nanoestructurados ( CeO2 ) depositadas por
CVD
Juan Peña*±, Mario F. García-Sánchez±, Guillermo Santana±, B. Marel Monroy
Peláez±.
*Instituto de Ciencias Nucleares ±Instituto de Investigaciones en
Materiales, Universidad Nacional Autónoma de México; Ciudad
Universitaria, Coyoacán 04510, México D.F., México
Resumen
La búsqueda de nuevas fuentes de energía no contaminantes es una de las tareas que se
enfrenta actualmente. Las SOFC aparecen como una de las alternativas en este sentido,
con el inconveniente de altas temperaturas de operación. En este trabajo se prepararon
películas delgadas de óxidos metálicos nanoestructurados ( CeO2 ) sobre sustratos de
silicio por RPU. El utilizar películas delgadas disminuye el valor de la resistencia y el
hecho de que sean nanoestructuradas permite una mejora de las propiedades eléctricas.
La segunda parte de nuestro trabajo consiste en describir cómo crecen los sólidos y
representar este proceso a través de un modelo que tome en cuenta la fenomenología
que tiene lugar cuando los átomos o moléculas se aglomeran para formar un sólido y
para ello utilizaremos el Método de la Matriz Estocástica.
P2.- The Stochastic Matrix Method and DNA
Juan Peña*, Roberto M, Rey G.
*Instituto de Ciencias Nucleares, &Facultad de Ciencias, Universidad Nacional
Autónoma de México; Ciudad Universitaria, Coyoacán 04510, México D.F., México
The stochastic matrix method can be used to study the configurational and
thermodynamic properties biomaterials in the work we are doing to us focus to discuss
how you can construct the stochastic matrix we describe the configuration of
deoxyribonucleic acid (DNA). Desoximbonucleico acid or DNA, consists of two chains
and can be described as a polymer composed of four monomers. The skeleton is the
same in all cases: a sugar (deoxyribose) and a phosphate. Skeletal bases emerge, which
may be adenine (A), guanine (G), cytosine (C) or thymine o. Each of the chains
integrates a molecule, because it is united by strong bonds (covalent). Two of the bases,
adenine and guanine, are similar in structure and called purines. The other two bases,
cytosine and thymine, are also similar and are called pyrimidines.
P3.- Velocity aucorrelation function of simple fluids for different repulsive terms
Alejandro Martínez Valencia, Benjamín Ibarra Tandi; Jorge López Lemus, Roberto
López Rendón,
Facultad de Ciencias, Universidad Autónoma del Estado de México. Instituto Literario
100, C.P. 50000, Toluca.
Some molecular dynamics simulations in a canonical ensemble for simple fluids were
performed. The Normalized Velocity Autocorrelation Function (NVACF) and the
Normalized Stress Autocorrelation Function (NSACF) were estimated when the
repulsive part of the potential is varied while the attractive part is fixed and vice-versa.
As an important result we found that, at high densities, the NVACF shows an
anomalous behavior (loop). This kind of phenomenon is more relevant for a higher
softness. This same behavior is observed for different ranges of the attractive well, for a
short range the effect is more intense and an opposite situation is observed for a longer
range. Finally, we can mention t hat the NSACF does not show this same trend.
P4.- RELATIVE ADSORPTION ON SURFACE TENSION OF TERNARY
MIXTURES OF SIMPLE FLUIDS
Gustavo Torres-García, Benjamín Ibarra-Tandi, Jorge López-Lemus
Universidad Autónoma del Estado de México, Instituto Literario 100, CP. 50000,
Toluca.
Some molecular dynamics simulations in the NVT ensemble were performed to analyze
ternary mixtures of simple fluids. Basically the interaction law among particles is the
Morse potential. An exploratory study was done for low temperatures where the relative
adsorption can be observed. The effect of particle-sizes on surface tension is revised by
molecular simulation. The A species (AA=1, AA=1) is more attractive than the B and C
species (BB=0.5, BB=1 and CC=1, CC=1.5). In this kid of systems there is a
competition between energetic and entropic processes. As an important result we
observe that the particles with larger size (CC=1.5) is localized on the liquid-vapor
interface of the A species instead of the B species. We can mention that the size does
matter.
P5.- Liquid-vapor interface of simple fluids interacting by Modified Morse
potential
Juana Guadalupe Bringas González[1]
, Jorge López Lemus[1]
, Benjamín Ibarra Tandi[1]
,
Pedro Orea[2]
[1]
Facultad de Ciencias, Universidad Autónoma del Estado de México, C.P. 50000,
Toluca [2]
Programa de Ingeniería Molecular, Instituto Mexicano del Petróleo. C.P. 07730,
Mexico D.F.
The liquid-vapor diagram and the surface tension of simple fluids were calculated by
means of Molecular Dynamics. The Morse function written as two Yukawa-type
potentials is the interaction law among particles. This same function was already
employed for estimating transport properties of liquid alkali metals in a homogeneous
fluid [F. Juan-Coloa et al. Mol. Sim. 33 (2007) 1167]. The surface tension and the
orthobaric densities related to this potential model are calculated for different cut-off
radii RC = 2.5s, RC = 4.0s and RC=5.0s. And as a relevant result we found that the
complete interaction is estimated by using the last cut-off distance. Furthermore it is
verified whether both Morse and modified Morse potential follow the Law of the
Corresponding State
P6.- LIQUID-VAPOR INTERFACE OF NITROGEN BY USING LATTICE
SUMS
Alexis Torres Carbajal, Benjamín Ibarra Tandi, Jorge López Lemus
Facultad de Ciencias, Universidad Autónoma del Estado de México, C.P. 50000,
Toluca, México.
Abstract
Some molecular dynamics simulations in the canonical ensemble were performed to
obtain the liquid-vapor equilibrium of molecular nitrogen. The dispersion interactions
were calculated by using the lattice sum method [1], which allows taking into account
the full interaction avoiding the dependence on the cut-off distance. Basically, we have
used the Cheung and Powles force field [2] for two cases: rigid and flexible models and
both of them showed an excellent agreement against experimental data. The liquid-
vapor equilibrium densities, surface tension and vapor pressure were estimated. As a
relevant result, we notice that the rigid nitrogen model offers the most reliable data, in
comparison to those obtained from a flexible model.
[1] J. López-Lemus and J. Alejandre, Mol. Phys. 100 (2002) 2983
[2] P.S.Y. Cheung, J.G. Powles, Mol. Phys. 30 (1975) 921
P7.- PHASE DIAGRAM OF BUTANE BY USING DIFFERENT FORCE FIELDS
Alejandro Villada Balbuena, Miguel Mayorga Rojas, Jorge López Lemus
Facultad de Ciencias, Universidad Autónoma del Estado de Mexico, Instituto Literario
100, C.P. 50000, Toluca.
Abstract
The liquid-vapor equilibrium densities of butane were estimated by means of Molecular
Dynamics Simulations. The Ewald Sums Method was used to estimate the long range
interactions of the Lennard-Jones potential. Some different Force Fields were
considered in order to compare their capabilities among them.
P8.- Physisorption phenomena in binary in mixtures of molecules models
C. Alejandro Campos Sánchez, Manuel Fuentes Herrera, Jorge López Lemus and
Benjamín Ibarra Tandi
Universidad Autónoma del Estado de México, Facultad de Ciencias, Departamento de
Física, Av. Instituto Literario No.100, Col. Centro, Toluca Estado de México. CP.
50000.
Abstract:
We developed molecular simulations in the NVT ensemble of molecular dynamic to
study the adsorption relative of a specie on the other in the liquid-vapour interface of a
binary mixture. This phenomena is called also physisorption or physical adsorption.
We calculated some interfacial properties such as the surface tension and density
profiles where we observed the physisorption phenomena. The molecular interaction
among molecules is modeled through of Morse modified potential.
P9.- 5 particles in a box with a step potential
Ariam Mora Hernández, Natalia Trujillo, Ruth Bustos, Norma Bagatella, Patricia
Padilla, Adrián Huerta
Facultad de Física e Inteligencia Artificial. Universidad Veracruzana
Abstract
In this study we propose a similar model to the originally proposed by Speedy, but
inspired in an experimental study using microgel particles [1]. In our model is possible
to obtain similar states with crystalline and amorphous ones, we perform computer
simulations to evaluate ―thermodynamic‖ and dynamical properties for the cases
a) and b) , where is the energy of the step potential. To
complement our work we perform similar experiments but using hidrogel particles, we
expect that our experimental updated results represent the case c) of our model;
and could be explored using event driven molecular dynamic simulations, similar to the
methodology proposed by José Alejandré and coworkers [2].
References
[1] Veronique Trappe (2009) ―Kinetics and Dynamics beyond arrest transitions‖.
[2] Chapela, Gustavo A., Martínez-Casas, Sergio E. and Alejandré, José (1984)
'Molecular dynamics for discontinuous potentials', Molecular Physics, 53: 1, 139-159.
P10.- Theoretical examination of the biochemical mechanisms of compound gene
regulation
Elisa Domínguez Hüttinger, Reiko Tanaka and Mauricio Barahona
Department of Bioengineering, Imperial College London, South Kensington Campus
London, SW7 2AZ
Compound gene regulation (CGR) is one of the main processes linking the cell with its
multi-factorial environment. During this process, two or more Transcription Factors
(TF) are activated by an environmental signal. This activation enables the binding of the
TF to a genetic sequence on the regulatory region of the target gene, affecting the levels
of expression of the gene. Here we study in silico the effect the different biochemical
mechanisms of CGR on the expression curve of the target gene. We propose a general
modeling framework from which particular mechanisms of CGR are derived and
simulated. The genotypic variability and the environmental fluctuations are explicitly
considered. The obtained results suggest that each biochemical mechanism of CGR
represents a robust biological strategy of compound control. Moreover, the shape of the
output function could be used to predict the underlying biochemical mechanism of CGR
from experimental data.
P11.- Theoretical method for film growth process nanostructured metal oxide thin.
Juan Peña * ±, Mario F. García-Sánchez±, B. Marel Peláez Monroy, S. Rojas&.
*Institute of Nuclear Sciences, ±Research Institute
Materials,F. Sciences, National Autonomous University of Mexico City
Universitaria, Coyoacán 04510, México DF, México
Summary
We used a theoretical model that describes the process agglomeration of atomic units
and that also allows us to study some important facts of the statistical process that occur
when the thin film is formed. In particular, by allowing several free valences are
saturated in a unique way in the different stages of agglomeration, in a first
approximation assume dendritic growth. The process becomes nonlinear, and must be
treated so that the same is self-consistent. The sites whose bonds are fully saturated in
every step become important and the final concentration abruptly changes at the
transition temperature for any value of concentration.
P12.- Characterization of nanochannels in the ε crystalline phase of sindiotactic
polystyrene
S. Figueroa-Gerstenmaier1
, G. Milano2
, O. Tarallo3
and G. Guerra2
1
División de Ciencias e Ingenierías, Campus León, Universidad de Guanajuato, León,
Gto., Mexico 2
Dipartimento di Chimica, NANOMATES and INSTM Research Unit, Università degli
Studi di Salerno, Fisciano SA, Italy 3
Dipartimento di Chimica, Università degli Studi di Napoli “Federico II”, Complesso
Universitario di Monte Sant'Angelo, Napoli NA, Italy
Recently, a polymeric nanoporous crystalline phase presenting channels parallel to the
chain axes has been discovered for a commercial and robust stereoregular, syndiotactic
polystyrene [1]. This is the orthorhombic ε phase [2], with a=1.61 nm, b=2.18 nm, and
c=0.79 nm and four chains per unit cell, which presents a minimum center-to-center
distance between channels of 1.36 nm and a density close to 0.98 g/cm3
, i.e., definitively
lower than the density of the corresponding amorphous phase (1.05 g/cm3
). The easy
processing to produce suitable morphologies, such as films, membranes and aerogels, gives
to this polymer advantages comparing to other crystalline frameworks.
The presence of these channels opens the possibility of using this material for many and
diverse applications; as for gas storage purposes, separation, micro chemical reactor and
more. Its usage for any potential application is fundamental to have a proper
characterization of the structure and the dimension of the channels. In particular, we are
interested on obtaining the dimensions (i. e. diameter, area, and volume) of these channels
and also on knowing the self-diffusion of light gases inside the polymer. In this work, we
have accomplished a double task; first, using crystallographic information about the
structure of the polymeric material, an atomistic model, and Molecular Dynamics, we have
calculated the diffusion behavior of He inside; second, using geometric measurements, we
have obtained the dimension of the channels forming the crystalline part of this polymer.
The results obtained from the two different methodologies about the empty space (channels)
agree very well.
Fig. 1 Trajectory path (line) of one atom of helium in the ε crystalline phase of syndiotactic polystyrene
(symbols showing positions of carbon atoms in the crystal) at 353 K and 1 bar by Molecular Dynamics. 0123450123456y (b) nmx (a) nm
Keywords: diffusion, Molecular Dynamics, helium. [1] P. Rizzo, C. Daniel, A. D. G. Del Mauro, G. Guerra, Chem. Mater. 19, 3864 (2007).
[2] V. Petraccone, O. Ruiz de Ballesteros, O. Tarallo, P. Rizzo, G. Guerra, Chem. Mater.
20, 3663 (2008). [email protected], División de Ciencias e Ingenierías, Campus León, Universidad de Guanajuato, Loma del Bosque 103, León (Gto.) 37150, Mexico.
P13.- Cluster formation and liquid-vapor coexistence of 2D Ionic Fluids
Gloria Arlette Méndez Maldonado1, Minerva González-Melchor
2, Honorina Ruiz-
Estrada1, José Alejandre
3.
Facultad de Ciencias Físico-Matemáticas1, Instituto de Física
2 ―Luis Rivera Terrazas‖,
Benemérita Universidad Autónoma de Puebla, Puebla, Pue. México, 72570.
Departamento de Química3, Universidad Autónoma Metropolitana-Iztapalapa, México
Distrito Federal, México, 09340.
A numerical study of two - dimensional binary mixture of charge discs is performed by
using molecular dynamic. The discs interact through the soft primitive model. We
report the liquid - vapor coexistence curve for the 1:1 symmetric mixture. We quantify
the formation of clusters by calculating the fraction of free ions and the cluster size
distribution in all cases for different states of density, temperature and charge
asymmetries.
P14.- STUDIES OF CHIRAL MOLECULAR SYSTEMS
Natali Martínez-Vara, José Antonio Moreno-Razo, Enrique Díaz-Herrera.
UNIVERSIDAD AUTÓNOMA METROPOLITANA – IZTAPALAPA
Av San Rafael Atlixco No.186, Col.Vicentina C.P.09340 Del. Iztapalapa México D.F.
In this work we study chiral molecular systems governed by intermolecular Chiral Gay-
Berne like potential [1,2,3]. On the basis of numerical calculations of Molecular
Dynamics in the NVT and NPT assemblies[4], we explore how the thermodynamic and
structural properties changes upon varying the chiral parameter, which controls the
chiral interaction potential. Fixing the chiral parameter (c*=1), we explore the topology
of the phase diagram Temperature vs density [5,6], the phases existing and its structural
properties change. Besides we show some characteristic chiral phases like Cholesteric
or chiral nematic (N*) and Blue Phases (BP) as a function of the chiral parameter.
[1] Memmer, R., Kuball, H.-G., and Schönhofer, A. (1993) Liquid Crystals 15(3), 345–
360.
[2] Gay, J. G. and Berne, B. J. Mar. 15 1981 Journal of the Chemical Physics 74(6).
[3] Memmer, R. (2001), NIC Symposium 2001, Proceedings, Vol. 9, pp. 325-334, 2002.
[4] Memmer, R. (1998) Ber. Bunsenges. Phys. Chem. 102(8), 1002–1010.
[5] Cañeda-Guzmán, E. Estudio de las propiedades estructurales y termodinámicas de
mezclas binarias de cristales líquidos confinados y/o en campo externo. Universidad
Autónoma Metropolitana - Iztapalapa febrero 2009.
[6] Moreno-Razo, J. A. Estudio Molecular de Mezclas Binarias con Interacciones
Esféricas y No-Esféricas. PhD thesis Universidad Autónoma Metropolitana –
Iztapalapa. Marzo 2007.
P15.- Thermodynamic Properties of Cholesterol in Lipid Membranes in an
Aqueous Solution.
Dr. Francisco Castro Román, Pedro Bautista Cabrera
Centro de Investigación y de Estudios Avanzados del IPN.
Av IPN 2508 Col. San Pedro Zacatenco México, D.F. C.P. 07360
Abstract:
Intracellular transport of cholesterol is of primary importance to different cell functions
and any dysfunction in its regulation can lead to various diseases like atherosclerosis,
for example. Cholesterol is an essential component of the plasma membrane in
vertebrates because it regulates its fluidity. As cholesterol can be transported through
vesicles or by other means within the cell, one would expect a uniform cholesterol
distribution along the different organelles in the cell. However, the cell keeps a high
gradient of cholesterol between the endoplasmic reticulum and the plasma membrane.
The challenge is then to understand the transport mechanisms that control homeostasis
of cholesterol in the cell.
By means of molecular dynamics simulations, and using the umbrella sampling
technique, the thermodynamic properties of phospholipid membranes with cholesterol
at different molar concentrations and different temperatures are studied. In particular,
the Gibbs free energy profiles for both the partitioning and flip-flop of cholesterol in the
lipid membrane are determined. For the partitioning of cholesterol in the lipid
membrane, the enthalpy and entropy component were also obtained. For the three
molar concentrations of cholesterol that were studied, the energy barrier for cholesterol
extraction decreases with increasing temperature. Also, we find that the partitioning of
cholesterol into the lipid membrane is enthalpy driven. In all the simulations the coarse-
grained MARTINI model [J. Phys. Chem. B, Vol. 111, No. 27, 2007] was used for
water, cholesterol and the phospholipid POPC
P16.- Computational Chemistry at UACH
María Elena Fuentes-Montero, Luz María Rodríguez-Valdez, Marco Antonio
Chávez-Rojo
Laboratorio de Química Computacional, Universidad Autónoma de Chihuahua,
Campus Universitario II, 31125 Chihuahua, México
In this work we review the computer simulation research recently developed in our
group. This includes the study of systems ranging from mesoscopic (colloidal
suspensions) to atomic scale. The first subject refers to the modelling of diffusion
properties of fluids in porous media. The porous matrix can be modelled as a collection
of obstacles (spherical, cilyndrical, etc.) or by means of an external potential that
confines the diffusing fluid into regions of lower energy. Here we present some model
systems studied with this technique.
The second subject deals with organic semiconductors systems. Organic
semiconductors based on π-conjugated systems are of great interest as active
components in the manufacture of optoelectronic devices, organic solar cells, organic
and electrochemical transistors, and recently, in biosensors. These compounds with
heterostructures and bulk-heterojunctions of electron donor-acceptor materials have
opened up a new route for photon-to-current conversion, and they can offer a potentially
inexpensive alternative to traditional silicon solar cells. The potentialities of the organic
semiconducting materials for photovoltaic conversion and their electronic properties can
be theoretically analyzed by UV-Vis absorption and emission spectra. These systems
are studied with all-electron Density Functional methods in order to calculate the
structural and electronic properties of interest such as: HOMO (highest occupied
molecular orbital), LUMO (lowest unoccupied molecular orbital), HOMO-LUMO GAP
energy in ground state, and electronic transitions in excited state.
The third subject is modeling mechanical properties of crystals. 1) Hydroxyapatite
(HAP) and fluorapatite(FAP) are essential components of dental enamel and bone. In
this paper we report a computational study of the elastic properties of HAP and FAP
using ab initio and forcefield techniques. We have obtained the HAP and FAP elastic
stiffness constants in hexagonal symmetry by fitting the Hooke law for both the energy-
strain and stress-strain relations. Our ab initio HAP stiffness constants differ from
previous calculations, but follow similar trends. The properties mismatch between HAP
and FAP is evidently too small to assume it directly responsible for the dental enamel
mechanical degradation with fluorosis disease. 2) Performing "computational
experiments" to explain the mechanisms of the electrical properties of real materials,
produce optimized properties in other compounds that are part of the same family of
perovskite phases and even extend it to other related families.
P17.- COMPUTATIONAL MODEL FOR THE FILTRATION PROCESS OF
APPLE JUICE
N. A. MARRUFO-HERNÁNDEZ, M. A. CHÁVEZ-ROJO, M. E. FUENTES-
MONTERO, L. M. RODRÍGUEZ-VALDEZ
Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua.
Nuevo Campus Universitario. Apartado Postal 1542-C. Chihuahua Chih. México.
ABSTRACT:
A computational model for the diffusion of apple juice solids through a membrane
during the filtering process is presented. The aim is to determine the optimum pore-size
distribution once the particle-size distribution is known. The proposed model system for
the membrane consists on a series of flat parallel surfaces with circular holes of
different sizes and random distribution. Thus, the relation between both the pore-size
and the particle-size distributions can be identified, in order to predict the particle-size
distribution of the clarified juice according to the desired sensory properties.
P18.- Fluid-solid transition in hard hyper-sphere systems.
C.D. Estrada, M. Robles
Centro de Investigación en Energía, UNAM
Priv. Xochicalco S/N, Col. Centro 62580, Temixco Mor. México.
Abstract
In this work we present a numerical study, based on molecular dynamics simulations, to
estimate the freezing point of hard spheres and hypersphere systems in dimension D=4,
5, 6 and 7. We have studied the changes of the Radial Distribution Function (RDF) as a
function of density in the coexistence region. We started our simulations from
crystalline states with densities above the melting point, and moved down to densities in
the liquid state below the freezing point. For all the examined dimensions (including
D=3) it was observed that the height of the first minimum of the RDF changes in a
continuous way around the freezing density and resembles a second order phase
transition. With these results we propose a numerical method to estimate the freezing
point as a function of the dimension D using numerical fits and semiempirical
approaches. We find that the estimated values of the freezing point are very close to
previously reported values from simulations and theoretical approaches up to D=6
reinforcing the validity of the proposed method. This was also applied to numerical
simulations for D=7 giving new estimations of the freezing point for this
dimensionality.
P19.- Linear relation between Joule-Thomson coefficient (to zero pressure) of
different substances
Authors: Alfredo González-Calderóna, Adrián Rocha-Ichante
a, Rodolfo Espíndola-
Herediab and Fernando del Río
a
Keyword: Joule-Thomson coefficient, ANC theory, softness parameter, experimental
data.
The ANC theory explained in a simple way the linear relation that exists between the
second virial coefficient of different substances; besides, provides a potential that has
been extensively studied in gaseous phase. These relation, in its reduced form, is
determined by the softness parameter of the ANC potential. In this study we extend the
application of the ANC theory to another thermodynamic property; to say, we present
the relation existing between the Joule-Thomson coefficient to zero pressure of different
substances. We show that the predictions of the theory agree with experimental data
from NIST and with data tabulated by other authors, for most substances studied, there
are a agree too, in order to show that the ANC parameters from the second virial
coefficient were successfully used. Finally, we used in our study a new analytical
formulate for the ANC second virial coefficient.
a Universidad Autónoma Metropolitana, unidad Iztapalapa, Av San Rafael Atlixco
No.186, Col.Vicentina C.P.09340 Del. Iztapalapa México D.F.
b Universidad Autónoma Metropolitana, unidad Azcapotzalco, Av. San Pablo No. 180,
Col. Reynosa Tamaulipas, C.P. 02200, México, D.F.
P20.- Two-body hydrodynamic correlation functions of three-particle colloidal
systems in harmonic potentials
Abstract
We study the third-body contribution on the two-body hydrodynamic correlation
functions in systems composed of three colloidal spheres; particles only interact via
hydrodynamic interactions (HI). Each colloid is trapped in an optical trap that we model
as a spring-like force in all directions. We analytically solve the problem of two and
three particles using the Rotne-Prager tensor by assuming that the tensor is always
constant. Using Brownian Dynamics simulations including HI without applying the
constant diffusion tensor approximation, we validate our analytical model. Our findings
indicate that the presence of the third particle affects the relaxation times of both auto-
and cross-correlation functions. Moreover, new features not seen in the cross-correlation
functions of two particles are observed. For instance, in the simplest particle
configuration, i.e., collinear configuration, we observe that the anti-correlation effects
relax faster and the dynamics of pair of particles becomes now cooperative.
P21.- Computer simulation of molecular diffusion in zeolites
Diana Zubiate-Jiménez, Luz María Rodríguez-Valdez, María Elena Fuentes-Montero,
Marco Antonio Chávez-Rojo
Universidad Autónoma de Chihuahua, Facultad de Ciencias Químicas.
Circuito Universitario 1, S/N, Campus Universitario 2.
In this work we propose a computer simulation technique to model the diffusion of a
fluid through a porous medium. The model consists of a cubic box with periodic
boundary conditions where the fluid particles diffuse under the effect of an external
potential which creates a periodic arrangement of interconnected cavities. To show the
technique developed in this work, we apply this model for the calculation of the
diffusion properties of a molecular fluid permeating a zeolite.
P22.- Two-body hydrodynamic correlation functions of three-particle colloidal
systems in harmonic potentials
Edith Cristina Euán Díaz, Fidel Córdoba Valdés, Ramón Castañeda Priego.
División de Ciencias e Ingenierías.
Universidad de Guanajuato
Abstract
We study the third-body contribution on the two-body hydrodynamic correlation
functions in systems composed of three colloidal spheres; particles only interact via
hydrodynamic interactions (HI). Each colloid is trapped in an optical trap that we model
as a spring-like force in all directions. We analytically solve the problem of two and
three particles using the Rotne-Prager tensor by assuming that the tensor is always
constant. Using Brownian Dynamics simulations including HI without applying the
constant diffusion tensor approximation, we validate our analytical model. Our findings
indicate that the presence of the third particle affects the relaxation times of both auto-
and cross-correlation functions. Moreover, new features not seen in the cross-correlation
functions of two particles are observed. For instance, in the simplest particle
configuration, i.e., collinear configuration, we observe that the anti-correlation effects
relax faster and the dynamics of pair of particles becomes now cooperative.
P23.- Electronic structure study using density functional theory in organic
dendrimers.
R. M. Gutiérrez-Pérez, M. A. Chávez Rojo, M. E. Fuentes Montero and L. M.
Rodríguez-Valdez.
1Facultad de Ciencias Químicas. Universidad Autónoma de Chihuahua.
Chihuahua, Chihuahua. México
Abstract
In this work is presented a quantum-chemical study of the electronic and structural
properties in pirrolic rings derivatives conformed by the arrangement of several
monomeric units, these -conjugated systems form dendrons attached to a central core.
The main objective of this theoretical study is defined if these derivatives can be
employed as semiconducting materials in the construction of photovoltaic devices.
Density Functional Theory (DFT) is used to determine the optimized geometries and the
electronic properties of the ground state, while transition energies and excited state
structures are obtained from Time Dependent Density Functional Theory (TD-DFT).
The hybrid B3LYP functional is used with Pople type 3-21G basis set with a
polarization function for all calculations. The DFT and TD-DFT calculations have been
performed using Gaussian 03W software package.
The obtained results show that three-dimensional (3D) conjugated architectures in
which the combination of triphenylamine (TPA) core with -conjugated rings dendrons,
present the best geometric and electronic characteristics to be employed as an organic
semiconductor material in photovoltaic devices.
Keywords: Organic Semiconductors, Dendrimers, Density Functional Theory.
Corresponding author e-mail: [email protected]
P24 .- STUDY OF THE EFFECTS OF THE IONIC SIZE ASYMMETRY IN THE
SPHERICAL ELECTRIC DOUBLE LAYER: SIMULATION AND THEORY.
AUTOR 1: Enrique González-Tovar.
Institución de adscripción del Autor 1: Instituto de Física, Universidad Autónoma de San Luis Potosí, México.
Dirección de la Institución del Autor 1: Álvaro Obregón 64, Centro Histórico, 78000 San Luis Potosí, S.L.P., México.
AUTOR 2: Martín Chávez-Páez.
Institución de adscripción del Autor 2: Instituto de Física, Universidad Autónoma de San Luis Potosí, México.
Dirección de la Institución del Autor 2: Álvaro Obregón 64, Centro Histórico, 78000 San Luis Potosí, S.L.P., México
AUTOR 3: Guillermo Iván Guerrero-García.
Institución de adscripción del Autor 3: Department of Materials Science and Engineering, Northwestern University, USA.
Dirección de la Institución del Autor 3: Evanston, Illinois 60208, USA.
Abstract:
In this work we investigate the structural and some thermodynamical properties of the
electric double layer around a spherical macroion immersed in monovalent or divalent
size-asymmetric salts. The ionic size ratio considered was 2 (i.e., with anions twice the
size of cations). Extensive Monte Carlo simulations and integral equations calculations
were performed in the primitive model of the electrolyte, and the resulting data were
compared with the predictions of the classical Poisson-Boltzmann (PB) equation. Near
the point of zero charge a layer of adsorbed cations is observed irrespective of the
macroion's charge sign. Also, for a weakly charged macroion, we detect the appearance
of charge reversal [1] and overcharging [2]. The importance of the ionic size asymmetry
in the double layer is then discussed in the light of some recent electrophoretic
experiments [3,4]. The HNC/HNC and HNC/MSA integral equations formalisms show
good concordance with Monte Carlo ―experiments,‖ whereas the notable limitations of
the point-ion PB approach is evidenced. Most importantly, the simulations confirm our
previous theoretical predictions of the non-dominance of the counterions in the size-
asymmetric spherical electric double layer [1], the appearance of anomalous curvatures
at the outer Helmholtz plane, and the enhancement of the charge reversal and screening
at high colloidal surface charge densities due to the ionic size asymmetry [5].
References
[1] G. I. Guerrero-García, E. González-Tovar, M. Lozada-Cassou, and
F. de J. Guevara-Rodríguez, J. Chem. Phys. 123, 034703 (2005).
[2] F. Jiménez-Ángeles and M. Lozada-Cassou, J. Phys. Chem. B 108, 7286 (2004).
[3] S. B. Johnson, P. J. Scales, and T. W. Healy, Langmuir 15, 2836 (1999).
[4] A. Dukhin, S. Dukhin, and P. Goetz, Langmuir 21, 9990 (2005).
[5] G. I. Guerrero-García, E. González-Tovar, and M. Chávez-Páez, Phys. Rev. E 80, 021501
(2009).
P25.- Dynamics of the active site, the gorge and the back door in the human
acetylcholinesterase and butyrylcholinesterase.
Cesar Millán-Pacheco, José Luis Gómez-Olivares, and Eduardo Jardón-Valadez
Departamento de ciencias de la Salud. Universidad Autónoma Metropolitana-Iztapalapa.
México D.F. México.
Abstract:
Cholinergic neuromuscular junctions transmits excitatory stimulus as acetylcholine
(ACh) is released from the presynaptic neuron (Soreq and Seidman, 2001). By
hydrolysis of the neurotransmitter the signaling flow is terminated, recovering the
excitable state. The acetilcholinestarase (AChE) selectively decompose ACh to produce
choline and acetate; whereas butirylcholinesterase (BuChE) hydrolyses diverse
substrates as aspirin, cocaine, heroine (Lockridge 1990; Li B, et al. 2005), and natural
choline esters as ACh, propionilcholine, and butirylcholine (Li, B. et al 2001;
Manoharan, et al. 2007). Interestingly, cholinesterases (ChEs) have coevolved in
vertebrates and invertebrates (Horiuchi Y. et al 2003). In vertebrates ChEs are located in
diverse tissues as blood vessels, liver, intestine, pancreas, and placenta (Jbilo et al.,
1994; Li, B. et al 2001; Manoharan, et al. 2007) suggesting rather diverse functions, for
instance, cellular proliferation, adhesion, amyloid assembly, and apoptosis (Soreq and
Seidman, 2001; Zhang et al, 2002). Hence, the enzymatic activity of AChE and BuChE
has been used to monitor pathological conditions such as cancer, Alzheimer’s disease,
diabetes type 2, and metabolic syndrome among others (Das, U.N. 2007; Rendell et al,
2005; Isik & Bozoglu, 2009; García-Ayllón M-S, 2010). Therefore, an understanding of
the enzymatic function at the molecular level may provide clues on the appropriate
diagnosis and therapeutics in pathological conditions. In this work, we present a
preliminary study of the protein dynamics based on ~100 ns molecular dynamics
simulations of both human AchE and BchE. In particular we characterized relevant
interactions in the active site, the gorge, and back and side doors in different ionic
concentrations.
P26.- Monte Carlo Simulations of a model of protein folding.
Diego Garrido Ruiz, David P. Sanders
Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de
México
Ciudad Universitaria, 04510 México D.F., México
We use Monte Carlo methods to study a simple model for protein folding, known as the
HP model. With the Metropolis algorithm, we aim to find the native state configuration,
that is, the minimum energy state, for a polymer of a certain length. With the Wang—
Landau algorithm, we estimate density of states of the system. We contrast and compare
the methods both for a 2D square lattice and a 2D triangular lattice.
P27.- Inhibition study of the SOD-Cu/Zn of Taenia solium by computational
methods
Ponciano García-Gutiérrez1, Abraham Landa
2, Roberto López-Rendón
1, and
Arturo Rojo-Domínguez1,3
1Departamento de Química. Universidad Autónoma Metropolitana-Iztapalapa. San
Rafael Atlixco 186. Col. Vicentina, 09340 México, D.F. 2Departamento de
Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma
de México, México D.F., 04510. 3Departamento de Ciencias Naturales. Universidad
Autónoma Metropolitana-Cuajimalpa. Pedro Antonio de los Santos 84. Col. San Miguel
Chapultepec. 11850 México, D.F. corresponding autor: [email protected]
Abstract
Currently, molecular docking programs
are commonly used to pose small
molecules on the surface of a three-
dimensional representation of the
protein structure. As the number of
protein X-ray structures has increased
dramatically in recent years,1 these
programs have became standard
computational tools used in structure-
based optimization of lead compounds.2
Increasingly, molecular docking
programs are being used to find novel
and potent inhibitors of the enzymatic
activity of proteins through virtual
screening of compound libraries.3
In this work, we present our results on the
use of computational methods of docking
using MOE® package
4 on an X-ray
diffraction structure in order to design,
purchase/synthesize and test some organic
molecules that inhibit the enzymatic
activity of superoxide dismutase of the
parasite Taenia solium (TsSOD-Cu/Zn).5
We used LeadQuest®6
as a database of
compounds with pharmacological
potential which yielded, after
conformational search, about 2 million
structures from about 50 thousand
original compounds. In this work we
present and analyze a list of potentially
inhibiting molecules of the TsSOD-Cu/Zn
activity, with the highest scores obtained
which will be in turn experimentally
evaluated.
Some molecules that have inhibition
activity against TsSOD-Cu/Zn in
micromolar concentration
2
1
1
1
1
1
1
1
1
1
Binding
site
-5.10
-7.09
-8.41
-8.58
-8.62
-9.50
-9.54
-9.76
-9.85
-9.97
Score
110
29
28
27
36
3
5
24
33
32
21
HB in
complexCompoundNo.
2
1
1
1
1
1
1
1
1
1
Binding
site
-5.10
-7.09
-8.41
-8.58
-8.62
-9.50
-9.54
-9.76
-9.85
-9.97
Score
110
29
28
27
36
3
5
24
33
32
21
HB in
complexCompoundNo.
N N
OO
O
O
3-{2-[8-(2-Indan-2-yl-acetyl)-2,8-diaza-spiro[4.5]dec-2-yl]-2-oxo-ethyl}-5-methoxy-indan-1-one
NH
O
O
N
N
O
O
1-(1H-Indol-3-yl)-2-[4-(4-methyl-2-oxo-5-phenyl-oxazolidin-3-yl)-piperidin-1-yl]-ethane-1,2-dione
SN
ON
N
N
O
O
3-(2-{1-[2-(7-Methyl-indan-4-yloxy)-acetyl]-piperidin-4-yl}-imidazol-1-ylmethyl)-3H-benzothiazol-2
-one
N
O
O
N
N
O
O
N
4-{8-[2-(3-Methoxy-phenyl)-acetyl]-2,8-diaza-spiro[4.5]decane-2-carbonyl}-1-methyl-5-pyridin-3-yl-py
rrolidin-2-one
N
S
N NH
HN
N
O
N
O
O
O
F
Benzo[1,2,5]oxadiazole-4-carboxylic acid N'-(2-{1-[2-(4-fluoro-phenyl)-acetyl]-piperidin-4-yl}-thi
azole-4-carbonyl)-hydrazide
HN
S
N N
O
O
N
O
1-Methyl-1H-pyrrole-2-carboxylic acid {2-[1-(1-oxo-but-3-ynyl)-piperidin-4-yl]-thiazole-4-carbonyl
}-amide
NH
N
N
S
O
HN
NH
F
O
O
F
2,4-Difluoro-benzoic acid N'-{2-[1-(2-1H-indol-3-yl-acetyl)-piperidin-4-yl]-thiazole-4-carbonyl}
-hydrazide
N N
OO
Prazicquantel
N
HN
NH
O
OS
Albendazole
N
N
O
OO
O
3-{2-Oxo-2-[8-(3-phenyl-propynoyl)-2,8-diaza-spiro[4.5]dec-2-yl]-ethyl}-3H-isobenzofuran-1-one
(1) Berman, H.; Henrick, K.; Nakamura, H.; Markley, J. L. The worldwide Protein Data Bank (wwPDB):
ensuring a single, uniform archive of PDB data. Nucleic Acids Res. 2007, 35, D301-D303.
(2) Lang, P. T.; Aynechi, T.; Moustakas, D.; Shoichet, B.; Kuntz, I. D.; Brooijmans, N.; Oshiro, C. M.,
Molecular docking and structure-based design. In Drug DiscoVery Research: New Frontiers in the Post-
Genomic Era; Huang, Z., Ed.; John Wiley & Sons, Inc.: Hoboken, NJ, 2007; pp 3-23.
(3) Muegge, I.; Oloff, S. Advances in virtual screening. Drug DiscoVery Today: Technol. 2006, 3, 405–
411.
(4) Chemical Computing Group, Inc. Molecular Operating Environment (MOE). CCG, Montreal,
Canada. 2007. http://www.chemcomp.com, accessed in February, 2008.
(5) Manuscript in press.
(6) LeadQuest Compound Library, Tripos, Inc.: 1699 South Hanley Roaad, St. Luis, Mo.
P28.- COMPUTER SIMULATION OF THE BIOSURFACTANT-HEXADECANE
INTERACTION
Ana Isela Santa Anna López, Guadalupe Virginia Nevárez Moorillón, María del Rosario
Peralta Pérez, Luz María Rodríguez Valdez, María Elena Fuentes Montero, Marco Antonio
Chávez Rojo.
Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua.
Circuito No.1 S/N, Nuevo Campus Universitario, 31125 Chihuahua, Chih.
In this work, we propose a computer simulation methodology to model the biosurfactant-
hexadecane interactions in the context of bioremediation of diesel contaminated soils. Due to
damages in storage tanks and pipelines, there can be leakage of hidrocarbons that can be
responsible of serious impact to the surrounding soil. By this, the contamination of soils by
diesel is an important issue to be adressed. Hexadecane can be considered a model hidrocarbon
because of its abundance in common fuels. Our proposal consists of two steps, the first one is the
determination of molecular properties (optimized geometry, charges, dipolar moments) of
hexadecane and biosurfactant using Gaussian 03W, the second step is the development of a
molecular dynamics code for the simulation of the water-hexadecane-biosurfactant mixture in
order to predict the mesoscopic structure of this system.
P29.- STUDY OF THE INTERACTION OF TWO OPPOSITELY CHARGED
POLYELECTROLYTES: COMPLEX FORMATION MECHANISM
Efrain Meneses Juárez1, Minerva González-Melchor
1, Cesar Márquez Beltrán
1, José Alejandre
2
1Instituto de Física ―Luis Rivera Terrazas‖, Benemérita Universidad Autónoma de Puebla, Apdo.
Postal J-48, 72570, Puebla, Pue., México. 2Departamento de Química, Universidad Autónoma
Metropolitana-Iztapala, Av. San Rafael Atlixco 186, Col. Vicentina, 09340, México DF, México.
E-mail: [email protected], [email protected]
We studied the conformational properties of polyelectrolytes in solution by using Dissipative
Particle Dynamics simulations (DPD), this method was developed to accomplish the task of
reaching larger lengths and longer simulation times than atomistic molecular dynamics
simulation [1], resulting in a mesoscopic description of the system. We assigned charge
distributions on DPD particles [2] and the electrostatic interactions between two of them were
calculated by employing the Ewald summation technique as described in reference [3]. The
systems studied consisted of a cationic polyelectrolyte, an anionic polyelectrolyte, the
corresponding counterions and the solvent molecules. We calculated conformational and
structural properties to quantify the formation of a complex [4]. In order to explore this behavior
we fixed the size of the cationic polymer and changed the length of the anionic chain. A
sequence of simulations for different lengths of the anionic polymer were conducted to analyze
the properties, and to determine if the complex formation occurred. Here we considered fully
ionized chains in water at room temperature. We also present the influence of salt on the systems
studied and then we compared these results with an experimental system of a complex of
polyelectrolytes of opposite charge.
Acknowledgments
We acknowledge financial support from VIEP-BUAP and PROMEP.
[1] P.J. Hoogerbrugge, J. M. V. A. Koelman, Simulating microscopic hydrodynamic phenomena
with dissipative particle dynamics, Europhys. Lett. 155 (1992).
[2] R. D. Groot, Electrostatic interactions in dissipative particle dynamics-simulation of
polyelectrolytes and anionic surfactants, J. Chem. Phys. 118, 11265 (2003).
[3] M. González-Melchor, E. Mayoral, M.E. Velázquez, J. Alejandre, Electrostatic interactions
in dissipative particle dynamics using the Ewald sums, J. Chem. Phys. 125, 224107 (2006).
[4] C. Márquez-Beltrán et al., manuscript in preparation (2010).
P30.- COMPUTATIONAL MODEL OF THE DIFFUSION OF PATHOGENS THROUGH
CERVICAL MOCUS.
César Hinojos Daniel, Luz María Rodríguez Valdez, María Elena Fuentes Montero, Marco
Antonio Chávez Rojo.
Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua.
Circuito Universitario No. 1, Nuevo Campus Universitario, 31125 Chihuahua, Chihuahua
Abstract
In a menstrual cycle the biophysical and biochemical properties of cervical mucus change due to
the variation in its composition which affects both fertility and the permeability to pathogens.
These properties depend on the mucines content, which are conformed by a polipeptide with
lateral chains of oligosacharides. Different proportions between these components give rise to a
variety of microstructures and viscoelastic properties. For this, the permeability of mucus for
different microstructures deserves to be studied. In this work we propose a brownian dynamics
methodology to model the diffusion of spherical particles in a porous matrix conformed by a
collection of long-cilyndrical obstacles that mimics the microstructure of cervical mucus. The
parameters that define the system (particle diameter, rods diameter, concentration, etc.) are taken
from experimental data available in the literature.
P31.- pH Influence in the Adsorption of Model Polymers Confined by Colloidal Particles
Studied by Mesoscopic Simulations
Francisco Alarcón, Armando Gama Goicochea and Elías Pérez
Centro de Investigación en Polímeros (Grupo COMEX) Marcos Achar Lobatón No. 2, Tepexpan,
55885 Acolman, Estado de México, Mexico and Instituto de Física, Universidad Autónoma de
San Luis Potosí Álvaro Obregón 64, 78000 San Luis Potosí, Mexico.
The pH influence in the adsorption of charged polymers onto neutral and charged colloids is
studied by adsorption isotherms. These isotherms are obtained using Monte Carlo (MC)
simulations in the Grand Canonical (GC) ensemble in combination with the mesoscopic
technique known as dissipative particle dynamics (DPD), where the electrostatic interactions are
calculated using the three-dimensional Ewald sum method with a modification proposed by Yeh
and Berkowitz for confined systems. In particular, our systems are confined by colloidal particles
which are modeled by effective walls forces and the electric charges on the colloids are putted it
explicitly. We showed that the behavior obtained in our simulations is consistent with the
experimental one. The adsorption cationic polymers is regulated by its pH in both surface either
neutral and electrostatic surface, for a low pH the adsorption was greater than higher pH, we
conclude that the polymer highly charged compromise the adsorption to the surface because the
electrostatic repulsion between the charged monomers
P32.- Dynamic Arrest in ionic solutions: Debye – Hückel limit
A. M. Aguilar Molina, G. A. Méndez Maldonado, H. Ruiz Estrada, J. Nito-Frausto.
Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Av. San
Claudio y 18 Sur, Col. San Manuel CP. 72570 Puebla, Puebla.
The self-consistent generalized Langevin equation (SCGLE) theory for mixtures is employed to
show the ergodic–non-ergodic transition in the restricted primitive model (RPM). We obtained
the phase diagram corresponding to the arrest states for charge points.
P33.- STRUCTURAL PROPERTIES OF GRAPHENE OXIDE SHEET OBTAINED BY
MOLECULAR SIMULATION
J. J. Hernández Rosas and 1E. Chigo Anota
Cuerpo Académico Ingeniería en Materiales-Facultad de Ingeniería Química de la Benemérita
Universidad Autónoma de Puebla, México.
Is studied through DFT theory at the LDA approximation the electronic properties of graphene
oxide sheet [1] using a cluster for this trapeciodal (C54H17+OH3+O+COOH) and rectangular
(C56H19+OH3+O+COOH) geometry. It follows the criteria of positive vibration frequencies for
structural stability.
It is observed from the results presented geometry influences the electronic transition conductor
(trapezius)-semiconductor (rectangular) [2], plus a considerable change in polarity (dipole
moment). Optimal geometry is not planar
[1] J. J. Hernández Rosas, R. E. Ramírez Gutiérrez, A. Escobedo Morales, and E. Chigo Anota,
J. Mol. Model. DOI: 10.1007/s00894-010-0818-1
C. Solanes Rivas, J. J. Hernández Rosas, A. Escobedo Morales and E. Chigo Anota submitted to
Carbon.
[2] C. Nava Contreras, H. Hernandez Cocoletzi, E. Chigo Anota, submitted to J. Mol. Model.
P34.- EFFECT OF THE VACANCIES AND DOPING IN THE ELECTRONIC
PROPERTIES OF GRAPHENE AND BORON NITRIDE OXIDES NANORIBBONS
1E. Chigo Anota, J. J. Hernández Rosas, and A. Escobedo Morales
Cuerpo Académico Ingeniería en Materiales-Facultad de Ingeniería Química de la Benemérita
Universidad Autónoma de Puebla, México.
We analyze by Density Functional Theory at the level Local Density Approximation and
Perdew-Wang parameterization for the exchange-correlation term effect on the electronic
properties that have the carbon monovacancy graphene oxide and monovacancias of boron and
nitrogen in boron nitride oxide sheet [1].
Furthermore analyze the electronic properties when doping with Nitrogen oxide graphene
[C53NH17 + (OH)3 + COOH + O] and doping with carbon boron nitride oxide with chemical
compositions [N26CB27H17 + (OH)3 + COOH + O] and [N27B26CH17 + (OH)3 + COOH + O]. We
have considered the criterion of minimum energy and vibrational frequencies non-negative for
structural stability.
Our calculations indicate that the carbon monovacancy graphene oxide cause total reconstruction
of the network and a 7.73% reduction in the polarity and remains semi-metal character. Whereas
when it is doped with 0.65% nitrogen reduces the polarity and maintain their semi-metal and
finally when analyzing the doping but the vacancy becomes a semiconductor and reduces the
polarity 23.45%.
While boron nitride oxide monovacancy maintains nitrogen and boron (for 4 situations in 2
configurations considered) reducing its polarity in a 53.66 and 41.22% (configuration C1) and
135.29 and 41.87% increase (configuration C2) holding semiconductor character in both cases,
except for C1 when presented monovacancy of N that behaves as a semi-metal.
[1] C. Solanes Rivas, J. J. Hernández Rosas, A. Escobedo Morales, E. Chigo Anota, submitted to
Carbon.
This work was partially supported by VIEP-BUAP (Grant No. CHAE-ING10-I), FIQ-BUAP
(2010-2011).
P35.- Multipolar Square-well Perturbation Theory, Simulation and Application to
CO and N2O.
Ana Laura Benavides*, Francisco Javier García-Delgado,
Dpto. Ingeniería Física, División de Ciencias e Ingenierías, Campus León,
Universidad de Guanajuato, Apdo. E-413, León, Guanajuato, 37150, México
Francisco Gámez, Santiago Lago, and
Dpto. Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide,
Ctra. de Utrera Km. 1, Seville 41013, Spain
Benito Garzón.
Dpto. Matemáticas, Física Aplicada y Fisicoquímica, Facultad de Farmacia,
University
San Pablo CEU, Madrid, Spain
ABSTRACT
New Gibbs ensemble simulation data for a polar fluid modeled by a square-well potential plus
dipole-dipole, dipole-quadrupole and quadrupole-quadrupole interactions are shown. The
multipolar square-well perturbation theory (MSW) (A. L. Benavides, Y. Guevara, and F. del
Río, Physica A 202, 420 (1994) is tested against these simulation data. It is found that the MSW
is able to reproduce qualitatively well the vapor-liquid phase diagram for different multipolar
moment strengths, except in the critical region. The MSW is also used to model the behavior of
molecules with multiple chemical bonds as carbon monoxide and nitrous oxide and we found
that with a suitable choice of the values of the intermolecular parameters, the vapor-liquid
equilibrium of these substances is well estimated.
P36.- Characterization of micros-ms dynamics of proteins using an analysis of chemical
shifts
Norma E. González-Díaz[1]
, Iris Serratos-Álvarez[2]
, Marco A Mora[2]
, and Roberto López-
Rendón[1]
[1] Facultad de Ciencias. Universidad Autónoma del Estado de México
[2] Departamento de Química, Universidad Autónoma Metropolitana-Iztapalap
Abstract
An approach is presented that allows a detailed, quantitative characterization of conformational
exchange processes in proteins on the micros-ms time scale. The approach relies on a combined
analysis of NMR relaxation rates and chemical shift changes and requires that the chemical shift
of the exchanging species can be determined independently of the relaxation rates. The
applicability of the approach is demonstrated by a detailed analysis of the conformational
exchange processes previously observed in the protein apo Pin1-WW Domain for which NMR
has revealed conformational dynamics of a flexible loop in the millisecond range. We sample
and cluster the free energy landscape using Markov State Models (MSM) with major and minor
exchange states with high correlation with the NMR relaxation data and low NOE violations.
These MSM are hierarchical ensembles of slowly interconverting, metastable macrostates and
rapidly interconverting microstates. These results suggest that conformational equilibria between
holo-like and alternative conformers pre-exist in the intrinsic dynamics of apo Pin1-WW. Our
work represents an important step towards building networks of inter-converting conformational
states and is generally applicable.
P37.- Oscillatory sliding of graphene nano-flakes over crystalline graphite surfaces
Guillermo Ibarra-Reyesa and José L. Rivera
a,b
aFacultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco
J. Mujica 1630, Morelia 58000, Michoacán
bInstituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito
Exterior, Ciudad Universitaria, Coyoacán, 04510,
México, D. F.
Experiments have shown that small graphene flakes in the nano scale after being
displaced from an equilibrated state, return to its original position in an oscillatory motion [1].
We carried out molecular dynamics simulations to study this phenomenon in an ideal system to
elucidate the mechanisms involved. The ideal system consisted of two graphene sheets of equal
sizes (same area), with different number of atoms as large as 40 thousand atoms. The simulation
setup contains a cell with non-periodic boundaries. The atoms of one of the graphene sheets are
frozen in space in order to mimic the conformation of a two dimensional graphite. Intermolecular
interactions are described by van der Waals forces, while intramolecular interactions involved
bond, valance angle, and dihedral interactions. The force field employed reproduces packing
parameters in fullerene systems.
We measured the oscillatory behavior computing the center of mass of each graphene
sheet, and we show the oscillatory behavior in terms of the separation of the two coordinates.
The oscillatory behavior of the nano-flakes starts out with large amplitudes, and decreases in a
period of picoseconds for the smaller systems, and nanoseconds for the larger systems. The
frequency of the oscillations shows magnitudes in the scale of Gigahertz. Similar to the behavior
of displaced concentric carbon nanotubes, the nano-flakes return to their original equilibrated
configuration, due to the unbalanced forces driving the motion [2]. The dispersion interactions
are the only contributor to these forces.
[1] Q. Zheng et al., Physic Review Letters, 2008, 100, 067205
[2] J. L. Rivera, C. McCabe, P. T. Cummings, Nano Letters, 2003, 3, 1001
P38.- Quantum Chemical Simulation of the Interaction between Flavonol and Functional
Monomers in Molecularly Imprinted Materials
Cristina Iuga1, Elba Ortíz
2, Luis Noreña
2
1 Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional
Autónoma de México, México D.F. 04510, México. 2
Departamento de Química Aplicada, Universidad Autónoma Metropolitana - Azcapotzalco,
México, D.F. 02200, México.
Sensing devices based on the molecularrly imprinted materials represents a useful tool for
analytical purposes, specially for determining solutes in hydrophobic samples (foods, gasolines,
cosmetics, etc.) without a separation step. Many of the compounds analyzed in these type of
samples are only soluble in organic solvents, and their determination usually requires a solvent
extraction step. However, direct analysis of the organic solvent extract may be possible using a
MIP-mediated technique.
A desirable model of MIPs should be based on accurate interactions between the
components, it should reflect the essential elements of the synthetic protocol, and it should be
able to reproduce experimental results. Theoretical chemistry can fundamentally advance our
ability to design and synthesize new MIPs with specific functions, providing a unique insight
into the system with detailed atomistic level, and therefore are able to explain and elucidate
microscopic behavior.
In this work, we have studied the interaction of the 3-hydroxyflavone (flavonol), as a
recognition element, with methacrylic acid and 4-vinylpyridine, as a pre-polymerization step in
the formation of molecularly imprinted polymers, under vacuum conditions and in the presence
of different solvents. Flavonol was chosen as a representative target compound because it is the
base member of a large family of compounds (flavonoids and anthocyanins) which are the
subject of extensive analysis in food samples. Quantum chemistry calculations were performed
at M052X/6-311++g(d,p) and MP2(FC)/6-311++g(d,p) levels. The binding characteristics of the
imprinted polymer were examinated in detail.
P39 .- Molecular Dynamics Simulation of organic molecules at liquid-vapor interface
Abel Venegas Castro, Jorge López-Lemus and Roberto López-Rendón.
Facultad de Ciencias. Universidad Autónoma del Estado de México.
We have performed molecular dynamics simulations at constant temperature to study the
properties of diethanolamine (DEA) at interface liquid-vapor. Our aims were evaluate the
performance of the newly developed force field for ethanolamines [Roberto Lopez-Rendon,
Marco A. Mora, Jose Alejandre, and Mark E. Tuckerman J. Phys. Chem. B, 2006, 110 14652-58]
to describe the interface liquid-vapor of DEA. The properties evaluates were the pressure vapor
and surface tension in a ranging of temperatures from 298 K to 550 K. In this region is where
applications industrial for DEA carried out. From both the surface tension and pressure vapor
results are good agreemente with experimental data. The force field reproduced within 1% the
experimental surface tension values and 2% the pressure vapor results.
P40.- Physicochemical Aspects of Metal Protection by Azoles as Corrosion Inhibitors:
Mercaptoimidazoles and Mercaptobenzoimidazoles Evaluation
Cristina Iuga1, Elba Ortíz
2, Antonio Campero
3
1Departamento de Fisica y Química Teórica, Facultad de Química, Universidad Nacional
Autónoma de México, México D.F. 04510, México.
2Departamento de Química Aplicada, Universidad Autónoma Metropolitana - Azcapotzalco,
México D.F. 02200, México.
3Departamento de Química, Universidad Autónoma Metropolitana - Iztapalapa, México D.F.
09340, México.
Organic inhibitors generally protect the metal from corrosion by forming a film on the
metal surface. Their effectiveness as corrosion inhibitors is related to their chemical composition,
spatial molecular structure, molecular electronic structure, surface charge density, and their
affinity for the metal surface. In addition, specific interaction between functional groups and the
metal surface and heteroatoms like oxygen, nitrogen, sulphur and phosphorus play an important
role in inhibition due to the free electron pairs.
Azoles such as imidazole and benzimidazole has been shown to possess good inhibition
characteristics against steel and copper corrosion, and has been used extensively as corrosion
inhibitors. The planarity of heterocycles and the presence of lone pair of electrons on
heterocyclic atoms are particularly important structural characteristics because they mainly
determine the adsorption of inhibitor molecules on metal surface. However, substituent groups
which enhance the electron-donating or electron-withdrawing properties of the active N atom on
the heterocyclic ring, would strengthen or weaken the interaction with the metal surface.
In the present study, the anticorrosive performance of 2-mercaptoimidazole and 2-
mercaptobenzimidazole were investigated using quantum chemistry methods. It has been shown
that the presence of the mercapto group enhanced corrosion inhibition, as compared to imidazole
and benzimidazole. Thus, the inhibition mechanism is likely to be related to the substituent
group.
P41.- Title
Néstor Valadez
Universidad Autónoma de Guanajuato
Abstract
The discrete perturbation theory (DPT) that was originally developped in the context of liquid
theories is applied to the case of colloidal suspensions. We analized two effective intermolecular
potentials: Hard-Core Attractive Yukawa (HCAY) and Asakura Oosawa (AO). Both potentials
have been used to model the effective interaction of proteins. The HCAY potential when
electrolyte is added to the protein suspension and the AO potential when a polymer is added. We
compared our results for the HCAY with Monte Carlo simulation data. We found that the fluid-
fluid transition for several inverse screening length parameters is qualitatively well predicted by
the DPT approach, except in the critical region. For the AO we compare with the Gast et al.
perturbation theory results and for different diameter ratios (colloid/polymer) and we found that
the DPT predictions are better than those of Gast et al. specially for the cases where this ratio is
greater than 1
P42.- "Molecular simulations with quantum algorithms."
Edmundo M. Carrera
Departamento de Química Universidad Autónoma Metropolitana-Iztapalapa. San Rafael Atlixco
No. 186, Col. Vicentina, C.P.09340, México, D.F. [email protected]
The simulation of quantum systems, as molecules, might be easier on computers using quantum
algorithms. In fact, quantum algorithms would provide a means of exploring new quantum
phenomena in chemical reactivity. I present a quantum walk and study it, taking into account the
effect of quantum statistics and quantum mechanical phenomena such as entanglement. Finally, I
show the Hund algorithm, which predicts the multiplicity of the ground state of diatomic
molecules.
P43.- INTERACTION BETWEEN THE GRAPHENE SHEET AND CHITOSAN:
ELECTRONIC PROPERTIES
Ahbdí Torres Soto and 1E. Chigo Anota
Cuerpo Académico Ingeniería en Materiales-Facultad de Ingeniería Química de la Benemérita
Universidad Autónoma de Puebla, México.
Analyzed using DFT theory at the level LDA approximation the interaction between the
graphene sheet represented by a cluster of the form (C54H18) [1] and the chitosan (using the
monomer unit), 3 geometric configurations was investigated: the first is parallel to the sheet by
the OH group, the second is perpendicular to the sheet by the NH2 group and the third is parallel
to the sheet by the hexagon of the monomer.
The structural stability criterion is followed by obtaining positive vibration frequencies.
The results show that the stable geometry is presented for sheet parallel to the OH group.
Subsequently obtain chemical reactivity, energy gap (HOMO-LUMO) and thermodynamic
properties.
[1] J. J. Hernández Rosas, R. E. Ramírez Gutiérrez, A. Escobedo Morales, E. Chigo Anota First
principles calculations of the electronic and chemical properties of graphene, graphane and
graphene oxide. J. Mol. Model.DOI: 10.1007/s00894-010-0818-1
This work was partially supported by VIEP-BUAP (Grant No. CHAE-ING10-I), FIQ-BUAP
(2010-2011).
P44 .- Ab-inito study of electron transport in 4-(3-nitro-4-tetrafluorophenythiolate-
ethynylphenylethynyl) benzenethiolate (S-FNPPB-o).
Sandra G. Hernandez-Rios1 L.Serrato-Villegas
2, M.T. Romero
3, P. Alonso-Davila
1 and M.
Gallo1
1 Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, Av. Manuel Nava
No. 6 Zona Universitaria, San Luis Potosí, S.L.P. C.P. 78210, e-mail: [email protected]
2Facultad de Ciencias Químicas, Universidad Autónoma de Coahuila, Blvd. Venustiano
Carranza s/n. Saltillo, Coahuila, México. C.P.25200
3 Facultad de Ciencias Físico-Matemáticas, Universidad Autónoma de Coahuila, Conjunto
Universitario Camporredondo, Edificio "D". C.P. 25000, Saltillo, Coahuila.
4 Centro de Investigación en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo
Industrial Chihuahua, Chihuahua México 31109
The electron transport of (S-FNPPB-o) molecules assembled in Au (111) electrodes, was study
using two approaches, in the first simple approach an electric field was applied to the pure
molecule, and in the second approach we use the Non-equilibrium Green Function Formalism
(NEGF) to calculate the current voltage I-V curve and Transmission function in the extended
system molecule plus electrodes.
We study the energy alignment of the Molecular Orbitals (MOs) with respect to an electrical
field, the spatial distribution of the frontier molecular orbitals, as wells as the energy alignment
of the MOs by the coupling of the S-FNPPB-o molecule with the gold electrodes. The spatial
distribution of the frontier orbitals (HOMO-LUMO) is an important factor in determining the
molecular wire conductance. Generally, a conducting channel is a molecular orbital that is fully
delocalized along the molecular backbone.
The NEGF calculations indicate that in the range of voltages applied, the current is related to
transmission through the LUMO orbital.
List of Confirmed Participants
1 Alberto Hernández Almada CINVESTAV [email protected]
2 José Juan Peña Leal ICN; IIM, Unam [email protected]
3 Marco Tulio Gallo Estrada Universidad Autonoma [email protected]
4 BRINGAS GONZALEZ JUANA GUADALUPE UAEM [email protected]
5 Andrés Cedillo UAM-I [email protected]
6 Claudia Aranda De la Teja UAM Iztapalapa [email protected]
7 POPA MARIANA VIRGINIA Universidad Autónoma del Estado de Hidalgo [email protected]
8 Alejandro Martinez Valencia UAEM [email protected]
9 Pedro Jesus Bautista Cabrera Cinvestav [email protected]
10 Karina Cruz Cruz UAM [email protected]
11 Gustavo Torres Garcia UAEM [email protected]]
12 Alejandra Maqueda Policarpo UAM [email protected]
13 Alexis Torres Carbajal UAEM [email protected]
14 Alejandro Villada Balbuena UAEM [email protected]
15 Edith Cristina Euán Díaz Universidad de Guanajuato [email protected]
16 Leon D Islas Suarez UNAM, Facultad de Medicina [email protected]
17 Jorge Lopez Lemus UAEM [email protected]
18 Noé de Jesús Atzin Cañas Universidad Autónoma [email protected]
19 Alejandro Cruz Campos Sánchez UAEM [email protected]
20 Manuel Fuentes Herrera UAEM [email protected]
21 Ariam Mora Hernández Universidad Veracruz [email protected]
22 Luisa Natalia Trujillo López Universidad Veracruz [email protected]
23 José de Jesús Hernández Rosas Benemerita Universidada Autonoma de Puebla [email protected]
24 Alejandra Montserrat Navarrete López UAM-Iztapalapa [email protected]
25 José Alejandro Piedras Pérez UAM [email protected]
26 Elisa Domínguez Hattinger Imperial College London [email protected]
27 David Alejandro Hernandez Velazquez Instituto de investi [email protected]
28 Orlando Guzman UAM-Iztapalapa [email protected]
29 Gabriel U. Gamboa Cinvestav [email protected]
30 José Juan Peña Leal ICN, Unam [email protected]
31 Juan Montes Perez FCFM-UAP [email protected]
32 Ernesto Chigo Anota FIQ-BUAP [email protected]
33 Susana Figueroa Gerstenmaier Division de Ciencias [email protected]
34 Cano Corona Israel UAM-I [email protected]
35 Hugo Andrés López Peña UAM-I [email protected]
36 Andrea Ruiz Millan Benemerita Universidad Autonoma de Puebla [email protected]
37 Gloria Arlette Méndez Maldonado Facultad de Ciencias [email protected]
38 Jorge Garza UAMI [email protected]
39 Rodrigo Lugo Frias UNAM. Facultad de Ci [email protected]
40 Mariano Mendez Chavez universidad autónoma [email protected]
41 Nelly Ma. de la Paz González Rivas UAM-I [email protected]
42 NATALI MARTÍNEZ VARA UNIVERSIDAD AUTÓNOMA [email protected]
43 Pedro Jesus Bautista Cabrera Cinvestav [email protected]
44 Rafael A. Zubillaga Luna UAMI [email protected]
45 Mayra Lozano Espinosa Universidad Autonoma [email protected]
46 Avelino Cortés Santiago Universidad Autonoma [email protected]
47 Hector Francisco Hernandez Corzo UAM-I [email protected]
48 MYRNA H. MATUS UNIVERSIDAD VERACRUZ [email protected]
49 Martín del Campo Ramírez Jorge UAM-I [email protected]
50 Jorge Alberto Nochebuena Hernández Universidad Autónoma [email protected]
51 Maria Elena Fuentes Montero Universidad Autónoma de Chihuahua [email protected]
52 Gabriel Moyocoyani Molina Espíritu UAM - Iztapalapa [email protected]
53 Fidelmar Lechuga Sanabria Instituto de Químic [email protected]
54 Julio Cesar Armas Perez Instituto de Quimica [email protected]
55 NORMA ALEJANDRA MARRUFO HERNANDEZ Universidad Autónoma de Chihuahua [email protected]
56 Erwin García Hernández UAM-I [email protected]
57 IRIS NATZIELLY SERRATOS ALVAREZ Universidad Auónoma [email protected]
58 Anaid Gabriela Flores Huerta Universidad Autónoma [email protected]
59 Sandra Guadalupe Hernandez Rios Universidad Autonoma [email protected]
60 Cesar Daniel Estrada Alvarez Centro de Investigac [email protected]
61 JOSE ADRIAN MARTINEZ GONZALEZ UNAM [email protected]
62 José Alfredo González Calderón UAM-I [email protected]
63 Adrián Rocha Ichante UAM Iztapalapa [email protected]
64 Francisco Jaramillo [email protected]
65 Marco Antonio Chávez Rojo Universidad Autónoma de Chihuahua [email protected]
66 César Hinojos Daniel Universidad Autónoma de Chihuahua [email protected]
67 LUZ MARÍA RODRÍGUEZ VALDEZ Universidad Autónoma de Chihuahua [email protected]
68 Octavio Cienega Cacerez UAMI [email protected]
69 Enrique Cañeda Guzmán Universidad Autónoma [email protected]
70 PATRICIA PLIEGO PASTRANA UNIVERSIDAD AUTONOMA [email protected]
71 Enrique Gonzalez Tovar Instituto de Fisica, [email protected]
72 Cristina Cuautli Mejia UAM Iztapalapa [email protected]
73 Juan Ramón Salazar Cano Facultad de Ciencias [email protected]
74 raul fuentes uam [email protected]
75 Ana Laura Benavides Universidad de Guana [email protected]
76 Cesar Millan-Pacheco Universidad Autonoma [email protected]
77 Diego Garrido Ruiz Departamento de Fís [email protected]
78 David P. Sanders Departamento de FÃs [email protected]
79 Ponciano Garcia Gutierrez UAM-Iztapalapa [email protected]
80 Ana Isela Santa Anna López Universidad Autónoma de Chihuahua [email protected]
81 Efrain Meneses Juarez Benemérita Universi [email protected]
82 César Hinojos Daniel Facultad de Ciencias [email protected]
83 Francisco Alarcón Oseguera Centro de Investigac [email protected]
84 Miriam Ordoñes Diaz UAMI [email protected]
85 Roberto Cruz Velazquez UAMI [email protected]
86 Roberto Cruz Velazquez uami [email protected]
87 Minerva Gonzalez Melchor BUAP [email protected]
88 Rubicelia Vargas Fosada UAM Iztapalapa [email protected]
89 HUMBERTO LAGUNA GALINDO UNIVERSIDAD AUTÓNOMA [email protected]
90 Pedro Orea IMP [email protected]
91 Ana Maria Aguilar Molina BUAP [email protected]
92 MENANDRO CAMARILLO UNIVERSIDAD AUTÓNOMA [email protected]
93 Raul Antonio Ortiz Merino Universidad Nacional [email protected]
94 Elsa Maria de la Calleja Mora Instituto de Ciencia [email protected]
95 Joe Zeferino Ramirez Ramirez UAMI [email protected]
96 Camilo Victoriano Fabiola Universidad Autonoma [email protected]
97 Ahbdi Torres Soto BUAP [email protected]
98 Luis Daniel Hernández Rodríguez BUAP [email protected]
99 Gustavo Adolfo Chapela Castañares UAMI CBI Fisia [email protected]
100 Karina Cruz Cruz UAM [email protected]
101 Paola Gonzalez Castelazo UAEH [email protected]
102 Benjamin Ibarra Tandi Universidad Autónom [email protected]
103 Guillermo Ibarra Reyes Facultad de Ingenier [email protected]
104 YAZMIN GUADALUPE ROSS GUZMAN INSTITUTO DE NEUROET [email protected]
105 Miguel Angel Balderas Altamirano Universidad Autonoma [email protected]
106 Edmundo Segundo Carrera Martinez UAMI [email protected]
107 AZALIA PATIÑO CASTILLO UAMI [email protected]
108 Alicia Lucrecia Lira Campos UAEM [email protected]
109 Cinthia Erika Sánchez Fuentes UAM Azcapotzalco [email protected]
110 Santiago Israel Castillo Esparza Instituto de FÃsica [email protected]
111 Juan Carlos Ruiz Pineda UAM I [email protected]
112 Rodrigo Toledo Hernández FES Zaragoza, UNAM [email protected]
113 Jorge Luis García Velasco FES-Zaragoza [email protected]
114 Norma González Díaz UAEMex [email protected]
115 Graciela Moreno Terrón UAEMex [email protected]
116 David Martínez Esquivel UAEMex [email protected]
117 Abel Venegas Castro UAEMex [email protected]
118 Armando Mejía Terrón UAEMex [email protected]
119 Mark Tuckerman New York University [email protected]
120 Hector Domínguez IIM-UNAM [email protected]
121 Margarida Telo da Gama Universidad de Lisboa, Portugal [email protected]
122 José Luis Rivera IIM-UNAM-Morelia [email protected]
123 Enrique Díaz UAM-Iztapalapa [email protected]
124 Jacqueline Quintana IQ-UNAM [email protected]
125 Pedro Leyva UAM-Iztapalapa [email protected]
126 Steve Plimpton Sandia National Labs, USA [email protected]
127 Porfirio Luis-Jiménez UAE-México [email protected]
128 Alejandro Gil U. de Guanajuato [email protected]
129 Iván Ortega ICF-UNAM [email protected]
130 Noé Mendoza ICF-UNAM [email protected]
131 Fernando Bresme Imperial College-London, UK [email protected]
132 Nina Pastor UAE-Morelos [email protected]
133 Roberto Lopez Rendon UAE-Mexico [email protected]
134 Jose Alejandre UAM-Iztapalapa [email protected]
135 Magdaleno Medina IF-UASLP [email protected]
136 leonardo david herrera zuniga UAM-Iztapalapa [email protected]
137 Mendoza Espinosa Paola Universidad Nacional Autónoma de México [email protected]
138 antonio leonel hernandez martinez Universidad Nacional Autónoma de México [email protected]
139 Edgar N Rojas Instituto de Invstig [email protected]
140 Dafne Azucena Uscanga Roldan Universidad Nacional Autónoma de México [email protected]
141 Francisco Castro Roman CINVESTAV-IPN [email protected]
142 GABRIEL ARTURO SOTO OJEDA UNIVERSIDAD VERACRUZ [email protected]
Organizing Committee
Roberto López-Rendón
Universidad Autónoma del Estado de México.
Tel.: 55-58044675, Ext 110
Email: [email protected]
José Alejandre
Universidad Autónoma Metropolitana-Iztapalapa
Tel.: 55-58044675, Ext 105
Email: [email protected]
Sponsors
Universidad Autónoma del Estado de México
Universidad Autónoma Metropolitana-Iztapalapa
Consejo Nacional de Ciencia y Tecnología
