Editor-in-Chief : V.K. Rastogi
|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 Manimarana, I Hubert Joea*, Daisy Bhatb and V K Rastogib,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.
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
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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