Research Article Crystal Growth and Characterization of a...
5
Hindawi Publishing Corporation Indian Journal of Materials Science Volume 2013, Article ID 680256, 4 pages http://dx.doi.org/10.1155/2013/680256 Research Article Crystal Growth and Characterization of a New NLO Material: p-Toluidine p-Toluenesulfonate M. Suresh, 1 S. Asath Bahadur, 2 and S. Athimoolam 3 1 Department of Physics, Er. Perumal Manimekalai College of Engineering, Hosur, Tamil Nadu 635 11, India 2 Department of Physics, Kalasalingam University, Krishnakoil, Tamil Nadu 626 190, India 3 Department of Physics, Anna University, Tirunelveli Region, Nagercoil, Tamil Nadu 629 004, India Correspondence should be addressed to M. Suresh; [email protected] Received 5 September 2013; Accepted 5 November 2013 Academic Editors: K. M. Garadkar and A. Kajbafvala Copyright © 2013 M. Suresh et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Single crystals of p-Toluidine p-Toluenesulfonate (PTPT), an organic nonlinear optical (NLO) material, have been grown by slow evaporation method at room temperature using ethanol as solvent. e crystal system was confirmed from the single crystal X-ray diffraction analysis. e functional groups were identified using FTIR spectroscopy. UV-Vis-NIR spectrum showed that the UV cut-off wavelength of PTPT occurs at 295 nm and it has insignificant absorption in the wavelength region of 532–800 nm. e SHG efficiency of PTPT was measured by employing Kurtz and Perry powder technique using a Q-switched mode locked Nd: YAG laser emitting 1064 nm for the first time and it was found to be 52% of standard KDP. ermal and mechanical properties of PTPT were examined by TG/DTA and Vickers microhardness test, respectively. 1. Introduction Materials with large nonlinear optical susceptibilities are of current interest in the area of harmonic generation and optical modulation. In recent years, some polar organic crystals, which form a noncentrosymmetric structure which exhibit second-order nonlinear optical properties that far surpassed those of the conventional materials, have led to the synthesis and evaluation of a wide range of potentially useful solids [1]. Materials showing high optical nonlinearity have potential applications in signal transmission, data stor- age, optical switching, laser printing, displays, inflorescence, photolithography, remote sensing, chemical and biological species detection, high resolution spectroscopy, medical diagnosis, and underwater monitoring and communication [2]. Different types of molecular and bulk materials have been examined for nonlinear optical properties. Organic nonlinear materials are attracting a great deal of attention, as they have large optical susceptibilities, inherent ultrafast response times, and high optical thresholds for laser power as compared with inorganic materials [3]. Organic molecules with significant nonlinear optical activity generally consist of a -electron conjugated structure. e conjugated - electron moiety provides a pathway for the entire length of conjugation under the perturbation of an external electric field. Fictionalization of both ends of the -bond systems with appropriate electron donor and acceptor group can increase the asymmetric electronic distribution in either or both the ground and excited states, thus leading to an increased optical nonlinearity [4–7]. In the present investigation, we report the growth and characterization especially the SHG efficiency of p-Toluidine p-Toluenesulfonate (PTPT) for the first time. e grown crystals have been subjected to the characterizations like XRD, FTIR, UV-vis, thermal analysis, powder SHG, and microhardness studies. 2. Material and Methods 2.1. Crystal Growth. e title compound was obtained by the addition of p-toluenesulfonic acid (0.02 mol) to a solution of p-Toluidine (0.02mol) in ethanol, in the stoichiometric ratio 1 : 1. Within a week, tiny crystals were formed due to the spontaneous nucleation. Optically transparent good quality
Transcript of Research Article Crystal Growth and Characterization of a...
Hindawi Publishing CorporationIndian Journal of Materials ScienceVolume 2013 Article ID 680256 4 pageshttpdxdoiorg1011552013680256
Research ArticleCrystal Growth and Characterization of a New NLO Materialp-Toluidine p-Toluenesulfonate
M Suresh1 S Asath Bahadur2 and S Athimoolam3
1 Department of Physics Er Perumal Manimekalai College of Engineering Hosur Tamil Nadu 635 11 India2Department of Physics Kalasalingam University Krishnakoil Tamil Nadu 626 190 India3 Department of Physics Anna University Tirunelveli Region Nagercoil Tamil Nadu 629 004 India
Correspondence should be addressed to M Suresh sureshmuthu23yahoocom
Received 5 September 2013 Accepted 5 November 2013
Academic Editors K M Garadkar and A Kajbafvala
Copyright copy 2013 M Suresh et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited
Single crystals of p-Toluidine p-Toluenesulfonate (PTPT) an organic nonlinear optical (NLO) material have been grown by slowevaporation method at room temperature using ethanol as solvent The crystal system was confirmed from the single crystal X-raydiffraction analysis The functional groups were identified using FTIR spectroscopy UV-Vis-NIR spectrum showed that the UVcut-off wavelength of PTPT occurs at 295 nm and it has insignificant absorption in the wavelength region of 532ndash800 nmThe SHGefficiency of PTPT was measured by employing Kurtz and Perry powder technique using a Q-switched mode locked Nd YAG laseremitting 1064 nm for the first time and it was found to be 52 of standard KDPThermal and mechanical properties of PTPT wereexamined by TGDTA and Vickers microhardness test respectively
1 Introduction
Materials with large nonlinear optical susceptibilities are ofcurrent interest in the area of harmonic generation andoptical modulation In recent years some polar organiccrystals which form a noncentrosymmetric structure whichexhibit second-order nonlinear optical properties that farsurpassed those of the conventional materials have led tothe synthesis and evaluation of a wide range of potentiallyuseful solids [1] Materials showing high optical nonlinearityhave potential applications in signal transmission data stor-age optical switching laser printing displays inflorescencephotolithography remote sensing chemical and biologicalspecies detection high resolution spectroscopy medicaldiagnosis and underwater monitoring and communication[2] Different types of molecular and bulk materials havebeen examined for nonlinear optical properties Organicnonlinear materials are attracting a great deal of attentionas they have large optical susceptibilities inherent ultrafastresponse times and high optical thresholds for laser poweras compared with inorganic materials [3] Organic moleculeswith significant nonlinear optical activity generally consist
of a 120587-electron conjugated structure The conjugated 120587-electron moiety provides a pathway for the entire length ofconjugation under the perturbation of an external electricfield Fictionalization of both ends of the120587-bond systemswithappropriate electron donor and acceptor group can increasethe asymmetric electronic distribution in either or both theground and excited states thus leading to an increased opticalnonlinearity [4ndash7] In the present investigation we report thegrowth and characterization especially the SHG efficiency ofp-Toluidine p-Toluenesulfonate (PTPT) for the first timeThegrown crystals have been subjected to the characterizationslike XRD FTIR UV-vis thermal analysis powder SHG andmicrohardness studies
2 Material and Methods
21 Crystal Growth The title compound was obtained by theaddition of p-toluenesulfonic acid (002mol) to a solutionof p-Toluidine (002mol) in ethanol in the stoichiometricratio 1 1 Within a week tiny crystals were formed due to thespontaneous nucleation Optically transparent good quality
2 Indian Journal of Materials Science
Figure 1 Grown Crystal of PTPT
NH3
CH3 CH3
minus+ SO3
middot
Figure 2 Molecular Structure of PTPT
crystals were used as seeds for further growth experimentsFor growth seed crystals were just immersed into theprepared solution Good quality crystals with characteristicshape and size of 10 times 5 times 2mm3 were obtained for 10 daysFigures 1 and 2 show the photograph of the grown crystalsand molecular structure of PTPT respectively
22 Characterization In order to confirm the grown crystalsingle crystal119883-ray diffraction studies were carried out usingENRAF NONIUS CAD4-F single 119883-ray diffractometer withMoK120572 (120582 = 071073 A) radiation The FTIR spectrumof the sample was recorded in the range 4000ndash450 cmminus1using Jasco Spectrometer (FTIR model 410) by KBr pellettechniqueTheUV-Vis-NIR analysis was carried out between200 and 800 nm covering the entire ultraviolet visible andnear infrared regions using the UV-1700 Shimadzu spec-trometer Vickerrsquos microhardness tester was used to assessthe mechanical properties of the grown crystal for variousloads ranging from 25 to 100 g The thermal behavior of thegrown crystal was studied using simultaneous TGDTA inthe temperature range of 20∘Cndash600∘C analyses using SEIKOTGDTA6200 analyzer in nitrogen atmosphere at the heatingrate of 20∘Cmin The SHG efficiency was measured byemploying Kurtz and Perry powder technique using a Q-switched mode locked Nd YAG laser emitting 1064 nm
3 Results and Discussion
31 Single Crystal XRD Studies Using the single crystal 119883-ray diffraction analysis the cell parameters of PTPT were
Table 1 FTIR spectral data of PTPT
S No Wave number (cmminus1) Tentative assignments1 3324b NH
3
+ Asymmetric Str2 2677m NHminus Str3 1694s NH
3
+ Asymmetric Str4 1694s SO3
minus Asymmetric bending5 1576m NH
3
+ Asymmetric deformation6 1502v Ring Str7 1448m NH
3
+ Asymmetric bending8 1295m CndashH bending in plane H bond9 1192m CndashH bending10 1156s SO
3
minus Symmetric Str11 1091w CndashH in plane deformation12 936s CndashC strSOminus Antisymmetric str13 856s CHminus deformation14 769b amp 743b NndashH deformation15 664w 621w amp 575w CndashC str16 769m NndashH deformation17 700w CndashC str18 559s COOminus deformation19 525m CndashC deformation20 452w CndashC deformation
obtained from least-squares refinement of the setting anglesof 25 reflections The XRD study reveals that the crystalbelongs to monoclinic system with lattice parameters of 119886 =5778(6) A 119887 = 9010(8) A and 119888 = 13320(7) A 119885 = 2and space group is P2
1 which is in agreement with those of
reported values [8]
32 Density Measurement The density of the crystal wasdetermined by the floatation technique (also called the sinkor swim technique) For the measurement of crystal densitycarbon tetrachloride of density 159 gmcm3 was used asdenser liquid and xylene of density 089 gmcm3 was usedas lower density liquid The density of the single crystal oftitle compoundwas determined as 1341(1) gmcm3 using thisfloatation technique and the theoretically expected density is1298 gmcm3
33 FTIR Analysis The FTIR spectrum recorder for thePTPT is shown in Figure 3 and its tentative assignments ofvibrational frequencies are given in the Table 1
34 UV-Vis-NIR Studies To analyze the optical properties ofgrown PTPT crystal UV-Vis transmittance was recorded Forthis polished sample of 1mm thick from the grown crystalwas used The recorded UV-Vis-NIR spectrum of PTPT isshown in Figure 4 The optical absorption study shows thatthe UV cut-off wavelength of PTPT occurs at 295 nm Itis well known that the efficient NLO crystal has an opticaltransparency at lower cut-off wavelength between 200 and400 nm [9] There is no significant absorption in the entirevisible region which reveals that it can find applications in the
Indian Journal of Materials Science 3
4000 3000 2000 100050
60
70
80
90
100
110
525
50621
93
769
4574
342
664
35
856
2393
627
1091
51
1156
12
1192
96
1295
93
1448
281504
215
765
216
941
6
2677
68
2884
02
3324
68
3618
77
3742
19
3843
43
Wavenumber (cmminus1)
T()
Figure 3 FTIR Spectrum of PTPT
100 200 300 400 500 600 700 800 900 1000
00
01
02
03
04
05
06
530
264
295
Wavelength (nm)
Abso
rbtio
n (a
u)
Figure 4 UV-Vis-NIR Spectrum of PTPT
optoelectronic devices Also the very low absorption around532 nm signifies the resistance of the grown crystal to laserinduced damage [10]
35 Thermal Studies TGADTA curve of PTPT is given inFigure 5 The DTA curve of PTPT indicates that the materialhas two sharp exothermic peaks at 2023∘C and 3203∘Cwhich represent the melting and decomposition pointsrespectively The TGA curve of PTPT indicates that thesample is stable from ambient up to 202∘CThe major weightloss between 202 and 320∘C is due to the decompositionThetotal weight loss of the sample is 96 at 320∘C
36 Microhardness Studies Hardness is one of the importantmechanical properties to determine the plastic nature andstrength of a material The well polished PTPT crystal wasplaced on the platform of the Vickerrsquos microhardness testerand the loads of different magnitudes were applied over afixed interval of time The hardness number was calculatedusing the relation 119867V = (18544119875)(119889
2) kgmm2 where 119875
6005004000300200100
100090080070060050040030020010000
96
DTA
1500
1000
500
000
minus500
minus1000
TG (
)
Temperature (∘C)
2023∘C 3203
∘C
5479∘C
Figure 5 TGADTA Curve of PTPT
is the applied load in kg and 119889 is the diagonal length of theindentation impression in micrometer The relation betweenhardness number (119867V) and load (119875) for PTPT is shown inFigure 6 The hardness increases gradually with the increasein load and above 100 g cracks were developed on the planeof the crystal due to the release of internal stresses generatedlocally by indentation Meyerrsquos index 119899 was calculated fromthe graph (Figure 7) plotted against log 119875 versus log 119889 Theslope of the line obtained from graph predicts that the valueof 119899 is greater than 2119867V should increase with the increase of119875 if 119899 gt 2 and decrease if 119899 lt 2 [11] Thus the 119899 value satisfiesthe observed result
37 Second Harmonic Generation Since PTPT has crystal-lized in a noncentrosymmetric space group a preliminarystudy of the powder SHG conversion efficiencywas carried AQ-switched Nd YAG laser beam of 1064 nm wavelength wasused with an input power of 44mJ pulseminus1 pulse width of10 ns and the repetition rate of 10Hz The crystals of PTPTwere ground to a uniform particle size of about 125ndash150 120583mand then packed in capillaries of uniform bore and exposedto the laser radiation A powder of potassium dihydrogenorthophosphate (KDP) with the same particle size wasused as the reference The output from the sample was
4 Indian Journal of Materials Science
20 30 40 50 60 70 80 90 100 110
65
70
75
80
85
90
95
Load P (g)
Har
dnes
s num
ber (
kgm
m2)
Figure 6 (119867V) versus load (119875)
180 182 184 186 188 190 192 194 196 19813
14
15
16
17
18
19
20
Log d
Log P
Figure 7 log 119875 versus log 119889
monochromated to collect only the second harmonic (120582 =532 nm) eliminating the fundamental and the intensity wasmeasured using a photomultiplier tube Second harmonicsignal of 558mV was obtained The standard KDP crystalsgave a SHG signal of 11mV for the same input energy Fromthismeasurement it is found that the SHG efficiency of PTPTis 52 of standard KDP
4 Conclusion
Single crystals of p-Toluidine p-Toluenesulfonate (PTPT)were grown from ethanol solution by slow evaporation ofthe solvent at room temperature The crystal system wasconfirmed from the single crystal 119883-ray diffraction analysisThe functional groups of the compound were determinedfrom FTIR spectrum Optical absorption studies show thatthe sample has minimum absorption in the entire visibleregion The melting point of PTPT was found to be 2023∘Cfrom the DTA curve The SHG efficiency of PTPT was foundto be 052 times than that of standard KDP
Acknowledgments
The authors thankDr P K Das IISc Bangalore for providingSHG testing facilities
References
[1] P N Prasad and D J Williams Introduction to NonlinearOptical Effects in Organic Molecules and Polymers John Wileyamp Sons New York NY USA 1991
[2] D S Chemla and J ZyssNonlinear Optical Properties of OrganicMolecules and Crystals Academic Press New York NY USA1987
[3] T Pal T Kar G Bocelli and L Rigi ldquoSynthesis growth andcharacterization of L-arginine acetate crystal a potential NLOmaterialrdquo Crystal Growth and Design vol 3 no 1 pp 13ndash162003
[4] R T Bailey G Bourhill F R Cruickshank D Pugh J NSherwood and G S Simpson ldquoThe linear and nonlinearoptical properties of the organic nonlinear material 4-nitro-4rsquo-methylbenzylidene anilinerdquo Journal of Applied Physics vol 73no 4 pp 1591ndash1597 1993
[5] C K Lakshmana Perumal A Arulchakkaravarthi N P Rajeshet al ldquoSynthesis crystal growth and FTIR NMR SHG studiesof 4-methoxy benzaldehyde-N-methyl-4-stilbazolium tosylate(MBST)rdquo Journal of Crystal Growth vol 240 no 1-2 pp 212ndash217 2002
[6] W Yu L Yang T-L Zhang et al ldquoCrystal structureand geometry-optimization study of 4-methyl-3101584051015840-dinitro-41015840-methyl benzylidene anilinerdquo Journal of Molecular Structure vol794 no 1-3 pp 255ndash260 2006
[7] K Srinivasan R Biravaganesh R Gandhimathi and PRamasamy ldquoGrowth and characterization of NMBA (4-nitro-41015840-methyl benzylidene aniline) single crystalsrdquo Journal of Crys-tal Growth vol 236 no 1-3 pp 381ndash392 2002
[8] R J Xu ldquo4-Methoxyanilinium iodiderdquo Acta CrystallographicaE vol 66 article o1794 2010
[9] Y le Fur R Masse M Z Cherkaoui and J F Nicuod ldquoCrystalstructure of ethyl-26-dimethyl-4(1H)-pyridinone trihydrate apotential nonlinear optical crystalline organic material trans-parent till the near ultraviolet rangerdquo Zeitschrift fur Kristallo-graphie vol 210 pp 856ndash860 1995
[10] V Krishnakumar R Nagalakshmi and P Janaki ldquoGrowthand spectroscopic characterization of a new organic nonlinearoptical crystal-8-hydroxyquinolinerdquo Spectrochimica Acta A vol61 no 6 pp 1097ndash1103 2005
[11] K Jagannathan S Kalainathan and T GnanasekaranldquoMicrohardness studies on 4-Dimethylamino-N-methyl 4-Stilbazolium Tosylate (DAST)rdquo Materials Letters vol 61 no23-24 pp 4485ndash4488 2007
Submit your manuscripts athttpwwwhindawicom
ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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NanoparticlesJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Biomaterials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
NanoscienceJournal of
TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Journal of
NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
CrystallographyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
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Advances in
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Smart Materials Research
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BioMed Research International
MaterialsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Nano
materials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal ofNanomaterials
2 Indian Journal of Materials Science
Figure 1 Grown Crystal of PTPT
NH3
CH3 CH3
minus+ SO3
middot
Figure 2 Molecular Structure of PTPT
crystals were used as seeds for further growth experimentsFor growth seed crystals were just immersed into theprepared solution Good quality crystals with characteristicshape and size of 10 times 5 times 2mm3 were obtained for 10 daysFigures 1 and 2 show the photograph of the grown crystalsand molecular structure of PTPT respectively
22 Characterization In order to confirm the grown crystalsingle crystal119883-ray diffraction studies were carried out usingENRAF NONIUS CAD4-F single 119883-ray diffractometer withMoK120572 (120582 = 071073 A) radiation The FTIR spectrumof the sample was recorded in the range 4000ndash450 cmminus1using Jasco Spectrometer (FTIR model 410) by KBr pellettechniqueTheUV-Vis-NIR analysis was carried out between200 and 800 nm covering the entire ultraviolet visible andnear infrared regions using the UV-1700 Shimadzu spec-trometer Vickerrsquos microhardness tester was used to assessthe mechanical properties of the grown crystal for variousloads ranging from 25 to 100 g The thermal behavior of thegrown crystal was studied using simultaneous TGDTA inthe temperature range of 20∘Cndash600∘C analyses using SEIKOTGDTA6200 analyzer in nitrogen atmosphere at the heatingrate of 20∘Cmin The SHG efficiency was measured byemploying Kurtz and Perry powder technique using a Q-switched mode locked Nd YAG laser emitting 1064 nm
3 Results and Discussion
31 Single Crystal XRD Studies Using the single crystal 119883-ray diffraction analysis the cell parameters of PTPT were
Table 1 FTIR spectral data of PTPT
S No Wave number (cmminus1) Tentative assignments1 3324b NH
3
+ Asymmetric Str2 2677m NHminus Str3 1694s NH
3
+ Asymmetric Str4 1694s SO3
minus Asymmetric bending5 1576m NH
3
+ Asymmetric deformation6 1502v Ring Str7 1448m NH
3
+ Asymmetric bending8 1295m CndashH bending in plane H bond9 1192m CndashH bending10 1156s SO
3
minus Symmetric Str11 1091w CndashH in plane deformation12 936s CndashC strSOminus Antisymmetric str13 856s CHminus deformation14 769b amp 743b NndashH deformation15 664w 621w amp 575w CndashC str16 769m NndashH deformation17 700w CndashC str18 559s COOminus deformation19 525m CndashC deformation20 452w CndashC deformation
obtained from least-squares refinement of the setting anglesof 25 reflections The XRD study reveals that the crystalbelongs to monoclinic system with lattice parameters of 119886 =5778(6) A 119887 = 9010(8) A and 119888 = 13320(7) A 119885 = 2and space group is P2
1 which is in agreement with those of
reported values [8]
32 Density Measurement The density of the crystal wasdetermined by the floatation technique (also called the sinkor swim technique) For the measurement of crystal densitycarbon tetrachloride of density 159 gmcm3 was used asdenser liquid and xylene of density 089 gmcm3 was usedas lower density liquid The density of the single crystal oftitle compoundwas determined as 1341(1) gmcm3 using thisfloatation technique and the theoretically expected density is1298 gmcm3
33 FTIR Analysis The FTIR spectrum recorder for thePTPT is shown in Figure 3 and its tentative assignments ofvibrational frequencies are given in the Table 1
34 UV-Vis-NIR Studies To analyze the optical properties ofgrown PTPT crystal UV-Vis transmittance was recorded Forthis polished sample of 1mm thick from the grown crystalwas used The recorded UV-Vis-NIR spectrum of PTPT isshown in Figure 4 The optical absorption study shows thatthe UV cut-off wavelength of PTPT occurs at 295 nm Itis well known that the efficient NLO crystal has an opticaltransparency at lower cut-off wavelength between 200 and400 nm [9] There is no significant absorption in the entirevisible region which reveals that it can find applications in the
Indian Journal of Materials Science 3
4000 3000 2000 100050
60
70
80
90
100
110
525
50621
93
769
4574
342
664
35
856
2393
627
1091
51
1156
12
1192
96
1295
93
1448
281504
215
765
216
941
6
2677
68
2884
02
3324
68
3618
77
3742
19
3843
43
Wavenumber (cmminus1)
T()
Figure 3 FTIR Spectrum of PTPT
100 200 300 400 500 600 700 800 900 1000
00
01
02
03
04
05
06
530
264
295
Wavelength (nm)
Abso
rbtio
n (a
u)
Figure 4 UV-Vis-NIR Spectrum of PTPT
optoelectronic devices Also the very low absorption around532 nm signifies the resistance of the grown crystal to laserinduced damage [10]
35 Thermal Studies TGADTA curve of PTPT is given inFigure 5 The DTA curve of PTPT indicates that the materialhas two sharp exothermic peaks at 2023∘C and 3203∘Cwhich represent the melting and decomposition pointsrespectively The TGA curve of PTPT indicates that thesample is stable from ambient up to 202∘CThe major weightloss between 202 and 320∘C is due to the decompositionThetotal weight loss of the sample is 96 at 320∘C
36 Microhardness Studies Hardness is one of the importantmechanical properties to determine the plastic nature andstrength of a material The well polished PTPT crystal wasplaced on the platform of the Vickerrsquos microhardness testerand the loads of different magnitudes were applied over afixed interval of time The hardness number was calculatedusing the relation 119867V = (18544119875)(119889
2) kgmm2 where 119875
6005004000300200100
100090080070060050040030020010000
96
DTA
1500
1000
500
000
minus500
minus1000
TG (
)
Temperature (∘C)
2023∘C 3203
∘C
5479∘C
Figure 5 TGADTA Curve of PTPT
is the applied load in kg and 119889 is the diagonal length of theindentation impression in micrometer The relation betweenhardness number (119867V) and load (119875) for PTPT is shown inFigure 6 The hardness increases gradually with the increasein load and above 100 g cracks were developed on the planeof the crystal due to the release of internal stresses generatedlocally by indentation Meyerrsquos index 119899 was calculated fromthe graph (Figure 7) plotted against log 119875 versus log 119889 Theslope of the line obtained from graph predicts that the valueof 119899 is greater than 2119867V should increase with the increase of119875 if 119899 gt 2 and decrease if 119899 lt 2 [11] Thus the 119899 value satisfiesthe observed result
37 Second Harmonic Generation Since PTPT has crystal-lized in a noncentrosymmetric space group a preliminarystudy of the powder SHG conversion efficiencywas carried AQ-switched Nd YAG laser beam of 1064 nm wavelength wasused with an input power of 44mJ pulseminus1 pulse width of10 ns and the repetition rate of 10Hz The crystals of PTPTwere ground to a uniform particle size of about 125ndash150 120583mand then packed in capillaries of uniform bore and exposedto the laser radiation A powder of potassium dihydrogenorthophosphate (KDP) with the same particle size wasused as the reference The output from the sample was
4 Indian Journal of Materials Science
20 30 40 50 60 70 80 90 100 110
65
70
75
80
85
90
95
Load P (g)
Har
dnes
s num
ber (
kgm
m2)
Figure 6 (119867V) versus load (119875)
180 182 184 186 188 190 192 194 196 19813
14
15
16
17
18
19
20
Log d
Log P
Figure 7 log 119875 versus log 119889
monochromated to collect only the second harmonic (120582 =532 nm) eliminating the fundamental and the intensity wasmeasured using a photomultiplier tube Second harmonicsignal of 558mV was obtained The standard KDP crystalsgave a SHG signal of 11mV for the same input energy Fromthismeasurement it is found that the SHG efficiency of PTPTis 52 of standard KDP
4 Conclusion
Single crystals of p-Toluidine p-Toluenesulfonate (PTPT)were grown from ethanol solution by slow evaporation ofthe solvent at room temperature The crystal system wasconfirmed from the single crystal 119883-ray diffraction analysisThe functional groups of the compound were determinedfrom FTIR spectrum Optical absorption studies show thatthe sample has minimum absorption in the entire visibleregion The melting point of PTPT was found to be 2023∘Cfrom the DTA curve The SHG efficiency of PTPT was foundto be 052 times than that of standard KDP
Acknowledgments
The authors thankDr P K Das IISc Bangalore for providingSHG testing facilities
References
[1] P N Prasad and D J Williams Introduction to NonlinearOptical Effects in Organic Molecules and Polymers John Wileyamp Sons New York NY USA 1991
[2] D S Chemla and J ZyssNonlinear Optical Properties of OrganicMolecules and Crystals Academic Press New York NY USA1987
[3] T Pal T Kar G Bocelli and L Rigi ldquoSynthesis growth andcharacterization of L-arginine acetate crystal a potential NLOmaterialrdquo Crystal Growth and Design vol 3 no 1 pp 13ndash162003
[4] R T Bailey G Bourhill F R Cruickshank D Pugh J NSherwood and G S Simpson ldquoThe linear and nonlinearoptical properties of the organic nonlinear material 4-nitro-4rsquo-methylbenzylidene anilinerdquo Journal of Applied Physics vol 73no 4 pp 1591ndash1597 1993
[5] C K Lakshmana Perumal A Arulchakkaravarthi N P Rajeshet al ldquoSynthesis crystal growth and FTIR NMR SHG studiesof 4-methoxy benzaldehyde-N-methyl-4-stilbazolium tosylate(MBST)rdquo Journal of Crystal Growth vol 240 no 1-2 pp 212ndash217 2002
[6] W Yu L Yang T-L Zhang et al ldquoCrystal structureand geometry-optimization study of 4-methyl-3101584051015840-dinitro-41015840-methyl benzylidene anilinerdquo Journal of Molecular Structure vol794 no 1-3 pp 255ndash260 2006
[7] K Srinivasan R Biravaganesh R Gandhimathi and PRamasamy ldquoGrowth and characterization of NMBA (4-nitro-41015840-methyl benzylidene aniline) single crystalsrdquo Journal of Crys-tal Growth vol 236 no 1-3 pp 381ndash392 2002
[8] R J Xu ldquo4-Methoxyanilinium iodiderdquo Acta CrystallographicaE vol 66 article o1794 2010
[9] Y le Fur R Masse M Z Cherkaoui and J F Nicuod ldquoCrystalstructure of ethyl-26-dimethyl-4(1H)-pyridinone trihydrate apotential nonlinear optical crystalline organic material trans-parent till the near ultraviolet rangerdquo Zeitschrift fur Kristallo-graphie vol 210 pp 856ndash860 1995
[10] V Krishnakumar R Nagalakshmi and P Janaki ldquoGrowthand spectroscopic characterization of a new organic nonlinearoptical crystal-8-hydroxyquinolinerdquo Spectrochimica Acta A vol61 no 6 pp 1097ndash1103 2005
[11] K Jagannathan S Kalainathan and T GnanasekaranldquoMicrohardness studies on 4-Dimethylamino-N-methyl 4-Stilbazolium Tosylate (DAST)rdquo Materials Letters vol 61 no23-24 pp 4485ndash4488 2007
Submit your manuscripts athttpwwwhindawicom
ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CorrosionInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Polymer ScienceInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CeramicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CompositesJournal of
NanoparticlesJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Biomaterials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
NanoscienceJournal of
TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Journal of
NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
CrystallographyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CoatingsJournal of
Advances in
Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Smart Materials Research
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MetallurgyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
BioMed Research International
MaterialsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Nano
materials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal ofNanomaterials
Indian Journal of Materials Science 3
4000 3000 2000 100050
60
70
80
90
100
110
525
50621
93
769
4574
342
664
35
856
2393
627
1091
51
1156
12
1192
96
1295
93
1448
281504
215
765
216
941
6
2677
68
2884
02
3324
68
3618
77
3742
19
3843
43
Wavenumber (cmminus1)
T()
Figure 3 FTIR Spectrum of PTPT
100 200 300 400 500 600 700 800 900 1000
00
01
02
03
04
05
06
530
264
295
Wavelength (nm)
Abso
rbtio
n (a
u)
Figure 4 UV-Vis-NIR Spectrum of PTPT
optoelectronic devices Also the very low absorption around532 nm signifies the resistance of the grown crystal to laserinduced damage [10]
35 Thermal Studies TGADTA curve of PTPT is given inFigure 5 The DTA curve of PTPT indicates that the materialhas two sharp exothermic peaks at 2023∘C and 3203∘Cwhich represent the melting and decomposition pointsrespectively The TGA curve of PTPT indicates that thesample is stable from ambient up to 202∘CThe major weightloss between 202 and 320∘C is due to the decompositionThetotal weight loss of the sample is 96 at 320∘C
36 Microhardness Studies Hardness is one of the importantmechanical properties to determine the plastic nature andstrength of a material The well polished PTPT crystal wasplaced on the platform of the Vickerrsquos microhardness testerand the loads of different magnitudes were applied over afixed interval of time The hardness number was calculatedusing the relation 119867V = (18544119875)(119889
2) kgmm2 where 119875
6005004000300200100
100090080070060050040030020010000
96
DTA
1500
1000
500
000
minus500
minus1000
TG (
)
Temperature (∘C)
2023∘C 3203
∘C
5479∘C
Figure 5 TGADTA Curve of PTPT
is the applied load in kg and 119889 is the diagonal length of theindentation impression in micrometer The relation betweenhardness number (119867V) and load (119875) for PTPT is shown inFigure 6 The hardness increases gradually with the increasein load and above 100 g cracks were developed on the planeof the crystal due to the release of internal stresses generatedlocally by indentation Meyerrsquos index 119899 was calculated fromthe graph (Figure 7) plotted against log 119875 versus log 119889 Theslope of the line obtained from graph predicts that the valueof 119899 is greater than 2119867V should increase with the increase of119875 if 119899 gt 2 and decrease if 119899 lt 2 [11] Thus the 119899 value satisfiesthe observed result
37 Second Harmonic Generation Since PTPT has crystal-lized in a noncentrosymmetric space group a preliminarystudy of the powder SHG conversion efficiencywas carried AQ-switched Nd YAG laser beam of 1064 nm wavelength wasused with an input power of 44mJ pulseminus1 pulse width of10 ns and the repetition rate of 10Hz The crystals of PTPTwere ground to a uniform particle size of about 125ndash150 120583mand then packed in capillaries of uniform bore and exposedto the laser radiation A powder of potassium dihydrogenorthophosphate (KDP) with the same particle size wasused as the reference The output from the sample was
4 Indian Journal of Materials Science
20 30 40 50 60 70 80 90 100 110
65
70
75
80
85
90
95
Load P (g)
Har
dnes
s num
ber (
kgm
m2)
Figure 6 (119867V) versus load (119875)
180 182 184 186 188 190 192 194 196 19813
14
15
16
17
18
19
20
Log d
Log P
Figure 7 log 119875 versus log 119889
monochromated to collect only the second harmonic (120582 =532 nm) eliminating the fundamental and the intensity wasmeasured using a photomultiplier tube Second harmonicsignal of 558mV was obtained The standard KDP crystalsgave a SHG signal of 11mV for the same input energy Fromthismeasurement it is found that the SHG efficiency of PTPTis 52 of standard KDP
4 Conclusion
Single crystals of p-Toluidine p-Toluenesulfonate (PTPT)were grown from ethanol solution by slow evaporation ofthe solvent at room temperature The crystal system wasconfirmed from the single crystal 119883-ray diffraction analysisThe functional groups of the compound were determinedfrom FTIR spectrum Optical absorption studies show thatthe sample has minimum absorption in the entire visibleregion The melting point of PTPT was found to be 2023∘Cfrom the DTA curve The SHG efficiency of PTPT was foundto be 052 times than that of standard KDP
Acknowledgments
The authors thankDr P K Das IISc Bangalore for providingSHG testing facilities
References
[1] P N Prasad and D J Williams Introduction to NonlinearOptical Effects in Organic Molecules and Polymers John Wileyamp Sons New York NY USA 1991
[2] D S Chemla and J ZyssNonlinear Optical Properties of OrganicMolecules and Crystals Academic Press New York NY USA1987
[3] T Pal T Kar G Bocelli and L Rigi ldquoSynthesis growth andcharacterization of L-arginine acetate crystal a potential NLOmaterialrdquo Crystal Growth and Design vol 3 no 1 pp 13ndash162003
[4] R T Bailey G Bourhill F R Cruickshank D Pugh J NSherwood and G S Simpson ldquoThe linear and nonlinearoptical properties of the organic nonlinear material 4-nitro-4rsquo-methylbenzylidene anilinerdquo Journal of Applied Physics vol 73no 4 pp 1591ndash1597 1993
[5] C K Lakshmana Perumal A Arulchakkaravarthi N P Rajeshet al ldquoSynthesis crystal growth and FTIR NMR SHG studiesof 4-methoxy benzaldehyde-N-methyl-4-stilbazolium tosylate(MBST)rdquo Journal of Crystal Growth vol 240 no 1-2 pp 212ndash217 2002
[6] W Yu L Yang T-L Zhang et al ldquoCrystal structureand geometry-optimization study of 4-methyl-3101584051015840-dinitro-41015840-methyl benzylidene anilinerdquo Journal of Molecular Structure vol794 no 1-3 pp 255ndash260 2006
[7] K Srinivasan R Biravaganesh R Gandhimathi and PRamasamy ldquoGrowth and characterization of NMBA (4-nitro-41015840-methyl benzylidene aniline) single crystalsrdquo Journal of Crys-tal Growth vol 236 no 1-3 pp 381ndash392 2002
[8] R J Xu ldquo4-Methoxyanilinium iodiderdquo Acta CrystallographicaE vol 66 article o1794 2010
[9] Y le Fur R Masse M Z Cherkaoui and J F Nicuod ldquoCrystalstructure of ethyl-26-dimethyl-4(1H)-pyridinone trihydrate apotential nonlinear optical crystalline organic material trans-parent till the near ultraviolet rangerdquo Zeitschrift fur Kristallo-graphie vol 210 pp 856ndash860 1995
[10] V Krishnakumar R Nagalakshmi and P Janaki ldquoGrowthand spectroscopic characterization of a new organic nonlinearoptical crystal-8-hydroxyquinolinerdquo Spectrochimica Acta A vol61 no 6 pp 1097ndash1103 2005
[11] K Jagannathan S Kalainathan and T GnanasekaranldquoMicrohardness studies on 4-Dimethylamino-N-methyl 4-Stilbazolium Tosylate (DAST)rdquo Materials Letters vol 61 no23-24 pp 4485ndash4488 2007
Submit your manuscripts athttpwwwhindawicom
ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CorrosionInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Polymer ScienceInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CeramicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CompositesJournal of
NanoparticlesJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Biomaterials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
NanoscienceJournal of
TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Journal of
NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
CrystallographyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CoatingsJournal of
Advances in
Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Smart Materials Research
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MetallurgyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
BioMed Research International
MaterialsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Nano
materials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal ofNanomaterials
4 Indian Journal of Materials Science
20 30 40 50 60 70 80 90 100 110
65
70
75
80
85
90
95
Load P (g)
Har
dnes
s num
ber (
kgm
m2)
Figure 6 (119867V) versus load (119875)
180 182 184 186 188 190 192 194 196 19813
14
15
16
17
18
19
20
Log d
Log P
Figure 7 log 119875 versus log 119889
monochromated to collect only the second harmonic (120582 =532 nm) eliminating the fundamental and the intensity wasmeasured using a photomultiplier tube Second harmonicsignal of 558mV was obtained The standard KDP crystalsgave a SHG signal of 11mV for the same input energy Fromthismeasurement it is found that the SHG efficiency of PTPTis 52 of standard KDP
4 Conclusion
Single crystals of p-Toluidine p-Toluenesulfonate (PTPT)were grown from ethanol solution by slow evaporation ofthe solvent at room temperature The crystal system wasconfirmed from the single crystal 119883-ray diffraction analysisThe functional groups of the compound were determinedfrom FTIR spectrum Optical absorption studies show thatthe sample has minimum absorption in the entire visibleregion The melting point of PTPT was found to be 2023∘Cfrom the DTA curve The SHG efficiency of PTPT was foundto be 052 times than that of standard KDP
Acknowledgments
The authors thankDr P K Das IISc Bangalore for providingSHG testing facilities
References
[1] P N Prasad and D J Williams Introduction to NonlinearOptical Effects in Organic Molecules and Polymers John Wileyamp Sons New York NY USA 1991
[2] D S Chemla and J ZyssNonlinear Optical Properties of OrganicMolecules and Crystals Academic Press New York NY USA1987
[3] T Pal T Kar G Bocelli and L Rigi ldquoSynthesis growth andcharacterization of L-arginine acetate crystal a potential NLOmaterialrdquo Crystal Growth and Design vol 3 no 1 pp 13ndash162003
[4] R T Bailey G Bourhill F R Cruickshank D Pugh J NSherwood and G S Simpson ldquoThe linear and nonlinearoptical properties of the organic nonlinear material 4-nitro-4rsquo-methylbenzylidene anilinerdquo Journal of Applied Physics vol 73no 4 pp 1591ndash1597 1993
[5] C K Lakshmana Perumal A Arulchakkaravarthi N P Rajeshet al ldquoSynthesis crystal growth and FTIR NMR SHG studiesof 4-methoxy benzaldehyde-N-methyl-4-stilbazolium tosylate(MBST)rdquo Journal of Crystal Growth vol 240 no 1-2 pp 212ndash217 2002
[6] W Yu L Yang T-L Zhang et al ldquoCrystal structureand geometry-optimization study of 4-methyl-3101584051015840-dinitro-41015840-methyl benzylidene anilinerdquo Journal of Molecular Structure vol794 no 1-3 pp 255ndash260 2006
[7] K Srinivasan R Biravaganesh R Gandhimathi and PRamasamy ldquoGrowth and characterization of NMBA (4-nitro-41015840-methyl benzylidene aniline) single crystalsrdquo Journal of Crys-tal Growth vol 236 no 1-3 pp 381ndash392 2002
[8] R J Xu ldquo4-Methoxyanilinium iodiderdquo Acta CrystallographicaE vol 66 article o1794 2010
[9] Y le Fur R Masse M Z Cherkaoui and J F Nicuod ldquoCrystalstructure of ethyl-26-dimethyl-4(1H)-pyridinone trihydrate apotential nonlinear optical crystalline organic material trans-parent till the near ultraviolet rangerdquo Zeitschrift fur Kristallo-graphie vol 210 pp 856ndash860 1995
[10] V Krishnakumar R Nagalakshmi and P Janaki ldquoGrowthand spectroscopic characterization of a new organic nonlinearoptical crystal-8-hydroxyquinolinerdquo Spectrochimica Acta A vol61 no 6 pp 1097ndash1103 2005
[11] K Jagannathan S Kalainathan and T GnanasekaranldquoMicrohardness studies on 4-Dimethylamino-N-methyl 4-Stilbazolium Tosylate (DAST)rdquo Materials Letters vol 61 no23-24 pp 4485ndash4488 2007
Submit your manuscripts athttpwwwhindawicom
ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CorrosionInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Polymer ScienceInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CeramicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CompositesJournal of
NanoparticlesJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Biomaterials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
NanoscienceJournal of
TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Journal of
NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
CrystallographyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CoatingsJournal of
Advances in
Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Smart Materials Research
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MetallurgyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
BioMed Research International
MaterialsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Nano
materials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal ofNanomaterials
Submit your manuscripts athttpwwwhindawicom
ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CorrosionInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Polymer ScienceInternational Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CeramicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CompositesJournal of
NanoparticlesJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Biomaterials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
NanoscienceJournal of
TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Journal of
NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
CrystallographyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CoatingsJournal of
Advances in
Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Smart Materials Research
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MetallurgyJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
BioMed Research International
MaterialsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Nano
materials
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal ofNanomaterials
