Wybren Jan Buma Molecular Photonics van ‘t Hoff Institute for Molecular Sciences University of...
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Transcript of Wybren Jan Buma Molecular Photonics van ‘t Hoff Institute for Molecular Sciences University of...
Wybren Jan BumaWybren Jan Buma
Molecular PhotonicsMolecular Photonics
van ‘t Hoff Institute for Molecular Sciences
University of Amsterdam
Mechanically interlocked molecules Mechanically interlocked molecules in the gas phase:in the gas phase:
isolated molecule spectroscopy and dynamicsisolated molecule spectroscopy and dynamics
MolMol PhotPhotEE
SS
MolMol PhotPhotEE
SS
Mechanically interlocked moleculesMechanically interlocked molecules
Two separate componentsNon-covalently bound
* macrocyclemacrocycle* threadthread → binding sitebinding site
Two separate componentsNon-covalently bound
* macrocyclemacrocycle* threadthread → binding sitebinding site
MolMol PhotPhotEE
SS
Mechanically interlocked moleculesMechanically interlocked molecules
Weak bond provides unique rotationalrotational and translationaltranslational degrees of freedom
that can be accessed in a controllablecontrollable and reversiblereversible manner
Weak bond provides unique rotationalrotational and translationaltranslational degrees of freedom
that can be accessed in a controllablecontrollable and reversiblereversible manner
MolMol PhotPhotEE
SS
ObjectivesObjectives
To control and manipulate molecular motors requires
* exploration of conformational landscapeconformational landscape
* knowledge of interactionsinteractions between the interlocked parts
* characterization relative movementrelative movement
To control and manipulate molecular motors requires
* exploration of conformational landscapeconformational landscape
* knowledge of interactionsinteractions between the interlocked parts
* characterization relative movementrelative movement
MolMol PhotPhotEE
SS
Gas phase experimentsGas phase experiments
* isolateisolate molecules from external effects (solvent)
* heating induces changes or decomposition
* laser desorptionlaser desorption technique to vaporize them
* cool molecules by entraining them into supersonic expansionsupersonic expansion
* isolateisolate molecules from external effects (solvent)
* heating induces changes or decomposition
* laser desorptionlaser desorption technique to vaporize them
* cool molecules by entraining them into supersonic expansionsupersonic expansion
MolMol PhotPhotEE
SS
High-resolution spectroscopyHigh-resolution spectroscopy
Laser desorption Mass spectrum
Excitation spectrum IR absorption spectrum
2800 3000 3200 3400 3600
0.0
0.2
0.4
0.6
0.8
1.0
Inte
nsity
IR wavenumbers (cm-1)
+ supersonic beam
NH
ONH
NH HN
HN
OO
OO
HN
O
NH
ONH
NH HN
HN
OO
OO
HN
O
MolMol PhotPhotEE
SS
SpectroscopySpectroscopy
supersonic beam
desorption laser
sample
nozzle
ions
Excitation & ionization laser
detector
1064 nm
MolMol PhotPhotEE
SS
Multiphoton ionization spectroscopyMultiphoton ionization spectroscopy
Mass-selected vibrationally-resolved excitation spectraMass-selected vibrationally-resolved excitation spectra
S0
S1
IE
Excitation energy
+ion
MolMol PhotPhotEE
SS
IR ion dip spectroscopyIR ion dip spectroscopy
~ 200 nsIR UV
S0 v=0
S1
IE
S0 v=1
+ion detection
NH NH stretch frequencies diagnostic of details (changes in)
hydrogen-bondinghydrogen-bonding
10
Ion signal
MolMol PhotPhotEE
SS
Does it work ?Does it work ?
macrocycle
rotaxane1148 amu
NH
ONH
NH HN
HN
OO
OO
HN
O
NH
ONH
NH HN
HN
OO
OO
HN
O
MolMol PhotPhotEE
SS
Problems to be tackled todayProblems to be tackled today
I. How does the macrocycle effect the conformational phase spaceconformational phase space of the thread ?
II. Can we characterise the interactionsinteractions between macrocycle and thread and find signatures for them ?
I. How does the macrocycle effect the conformational phase spaceconformational phase space of the thread ?
II. Can we characterise the interactionsinteractions between macrocycle and thread and find signatures for them ?
MolMol PhotPhotEE
SS
Building blocks in the gas phaseBuilding blocks in the gas phase
N
O
N
O
N
OO
NH
NH
O
O
N
OO
NH
NHPh
Ph
Ph
Ph
MolMol PhotPhotEE
SS
Excitation spectrum threadExcitation spectrum thread
origin
6b01
101
1201
9a01
6b0110
1
6b01120
1
N
O
N
O
MolMol PhotPhotEE
SS
Excitation spectrum threadExcitation spectrum thread
37800 37850 37900 37950 38000 38050 38100 38150 38200
Inte
nsit
y
one-photon energy (cm-1)37800 37850 37900 37950 38000 38050 38100 38150 38200
Inte
nsit
y
one-photon energy (cm-1)
MolMol PhotPhotEE
SS
Low-frequency vibrations threadLow-frequency vibrations thread
FFTFFT
49 cm-1 12 cm-1
MolMol PhotPhotEE
SS
Cooling conditionsCooling conditions
xenon
argon
~30 cm-1
~12 cm-1
MolMol PhotPhotEE
SS
Molecular motors in the gas phaseMolecular motors in the gas phase
N
OO
NH
NH
O
O
N
OO
NH
NHPh
Ph
Ph
Ph
193
nm io
niza
tion
MolMol PhotPhotEE
SS
Molecular motors in the gas phaseMolecular motors in the gas phase
~30 cm-1
~10 cm-1
Direct view on conformational phase space restrictionconformational phase space restriction by macrocycle
MolMol PhotPhotEE
SS
Mechanically interlocked moleculesMechanically interlocked molecules
NH
O
NH
HN
O
HN
O O
NH
ONH
NH HN
HN
OO
OO
HN
O
NH
ONH
NH HN
HN
OO
OO
HN
O
MolMol PhotPhotEE
SS
REMPI excitation spectroscopy: macrocycleREMPI excitation spectroscopy: macrocycle
NH
O
NH
HN
O
HN
O O
MolMol PhotPhotEE
SS
Ion-dip spectroscopy: macrocycleIon-dip spectroscopy: macrocycle
37200 37400 37600 37800 38000 38200 38400 38600
0.0
0.2
0.4
0.6
0.8
1.0
Nor
mal
ized
Int
ensi
ty
one-photon energy (cm-1)
NH
O
NH
HN
O
HN
O OC-H N-H
MolMol PhotPhotEE
SS
Ion-dip spectroscopy: rotaxaneIon-dip spectroscopy: rotaxane
NH
O
NH
HN
O
HN
O O
MolMol PhotPhotEE
SS
NH.....O=C
NH thread
Ion-dip spectroscopy: rotaxaneIon-dip spectroscopy: rotaxane
NH
ONH
NH HN
HN
OO
OO
HN
O
NH
ONH
NH HN
HN
OO
OO
HN
O
NH macrocycle
MolMol PhotPhotEE
SS
Present experimentsPresent experiments
IR-UV hole-burning spectroscopy at Free Electron Laser for Infrared eXperimentsFree Electron Laser for Infrared eXperiments
(FELIX)
Far IR (30 - 2000 cm-1) (C=O, fingerprint region)(C=O, fingerprint region)brings within reach:
- detailed view on conformational landscape
- vibrations of macrocycle with respect to the thread (< 400 cm-1)
IR-UV hole-burning spectroscopy at Free Electron Laser for Infrared eXperimentsFree Electron Laser for Infrared eXperiments
(FELIX)
Far IR (30 - 2000 cm-1) (C=O, fingerprint region)(C=O, fingerprint region)brings within reach:
- detailed view on conformational landscape
- vibrations of macrocycle with respect to the thread (< 400 cm-1)
MolMol PhotPhotEE
SS
ConclusionsConclusions
We can bring supramolecular assemblies We can bring supramolecular assemblies in the gas phase and perform in the gas phase and perform high-resolution spectroscopyhigh-resolution spectroscopy
Influence of macrocycle on conformational phase space thread
Conformational flexibility available to assembly
We can bring supramolecular assemblies We can bring supramolecular assemblies in the gas phase and perform in the gas phase and perform high-resolution spectroscopyhigh-resolution spectroscopy
Influence of macrocycle on conformational phase space thread
Conformational flexibility available to assembly
MolMol PhotPhotEE
SS
UvAUvAAnouk RijsAnouk Rijs
Dick Bebelaar
UC Santa BarbaraUC Santa BarbaraAli Abu-RiziqBridgit Crews
Mattanjah de VriesMattanjah de Vries
University of EdinburghUniversity of EdinburghDavid Leigh
UvAUvAAnouk RijsAnouk Rijs
Dick Bebelaar
UC Santa BarbaraUC Santa BarbaraAli Abu-RiziqBridgit Crews
Mattanjah de VriesMattanjah de Vries
University of EdinburghUniversity of EdinburghDavid Leigh
FundingFunding
NWONWOEC-TMR (RTN)EC-TMR (RTN)
EC-FETEC-FETEC-NMP EC-NMP
EC-Marie CurieEC-Marie Curie