AJP	ISSN : 0971 – 3093 Vol  22,  No. 1 , January-March ,  2013

Vol. 22, No. 1 (2013) 1-10

Vibrational spectra and density functional theoretical calculations on the NLO crystal DL-Valinium trifluoroacetate

 

D Manimaran^a, I Hubert Joe^a*, Daisy Bhat^b and V K Rastogi^b,c

^aCentre for Molecular and Biophysics Research, Department of Physics, Mar Ivanios College, Thiruvananthapuram-695 015, India.

^bR D Foundation Group of Institutions, NH-58, Kadrabad (Modinagar ), Ghaziabad, India

^cIndian spectroscopy society, K.C 68/1, Old Kavi Nagar, Ghaziabad- 201 002, U.P, India.

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Good optical quality single crystal of DL-Valinium trifluoroacetate (VLTFA) was grown by slow evaporation technique. The grown crystal was characterized by FT-IR and FT-Raman spectra and analyzed. The DFT computations were performed at B3LYP level with 6-31G(d,p) basis set to derive molecular structural parameters, vibrational wavenumbers, intensities, atomic charges distribution of VLTFA molecule. Vibrational analysis was used to investigate O-H …O=C and N–H…O=C hydrogen bonding interactions. Mulliken population analysis, hyperpolarizability and HOMO-LUMO energy gap are calculated by density functional theory. © Anita Publications. All rights reserved.

Total Refs: 33

Asian Journal of Physics

Vol. 22, No. 1 (2013) 97-100

DSC and optical texture studies of a nematic liquid crystal mixture

 

Rajbir Singh*, Jitendra Kumar** and K K Raina***

¹Department of Physics, Meerut College, Meerut-250 001, India
²Department of Applied Sciences, IIMT Engineering College, Meerut-250 001,
***School of Basic and Material Sciences, Thapar Institute of Engineering and Technology, Patiala-147 004, India

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Phase transition measurements have been taken using differential scanning calorimeter (DSC) and optical texture techniques of a nematic liquid crystal mixture (E-201) during heating cycle. The thermodynamic parameters such as the enthalpy (ΔH), entropy (ΔS) latent heat and heat capacity (Cp) have been determined. The optical texture of nematic liquid crystal mixture depends on the temperature and magnitude of the dc voltage applied to the cell geometry. © Anita Publications. All rights reserved.
Keywords: DSC, Nematic liquid crystal mixture, Optical Texture.

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