In this paper we report the dc Kerr constant and the pretransitional temperature of a polar nematic liquid crystal 4-(trans-4'-4'-n-pentylcyclohexy)- benzonitrile (PCH-5). The observed second-order pretransitional temperature T* from our measurements is found to be 1.2 °C below the first-order nematic to isotropic transition temperature. The dependence of the Kerr constant on (T-T*)-1 is found to be in good agreement with the predictions of the Landau-de Gennes model. The highest value of the Kerr constant observed at 632.8 nm is found to be 9.737×10-11 m V-2, corresponding to a temperature of 55.3 °C. © 1992 The American Physical Society.

Tetali A. Prasada Rao

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Physical Review A

Morpholinium dihydrogenphosphate (MDP) single crystals were synthesized, and were subsequently grown by controlled evaporation technique at room temperature for nonlinear optical applications. The grown crystal, which belongs to the monoclinic system with the space group P21, was subjected to single crystal X-ray diffraction to confirm the structure. UV–vis–NIR spectroscopy was done on the grown crystal and it showed good optical transparency in the entire visible region with a minimum cut-off wavelength of 289 nm. The optical band gap was computed as a function of photon energy using Tauc's plot. The refractive index of the grown crystal was determined using a Metricon Prism Coupler. The thermogravimetric (TG) and differential thermal analysis (DTA) traces disclosed the thermal stability of the compound. The mechanical strength of the crystal was investigated by a Vickers microhardness tester. Dielectric constant and dielectric loss were calculated and plotted as a function of frequency at different temperatures. The second harmonic conversion efficiency was determined using the Kurtz–Perry powder technique, and the efficiency was found to be 1.2 times greater than that of standard KDP. © 2016 Elsevier B.V.

Journal of Crystal Growth

Growth and characterization of morpholinium dihydrogenphosphate single crystal

A new organic stilbazolium derivative crystal 2-[2-(3-hydroxy-4-methoxy-phenyl)-vinyl]-1-methyl-pyridinium naphthalene-2-sulfonate dehydrate (C25H23NO5S·2H2O) (VSNS) was synthesized successfully.

RSC Adv.

Investigation of synthesis, crystal structure and third-order NLO properties of a new stilbazolium derivative crystal: a promising material for nonlinear optical devices

The performance of a high-voltage pulse measuring system based on the Kerr effect is investigated with benzoyl chloride, o-nitrotoluene, acetophenone, acetonitrile, benzaldehyde and ethyl methyl ketone for the first time along with nitrobenzene and acetone that are well known. These investigations have been carried out using high-voltage pulse fields ranging from 4*105 V m-1 to 107 V m-1. The experimentally determined electric field from the Kerr signal and the applied field show good agreement.

Measurement Science and Technology

A high-voltage pulse measuring system based on the Kerr effect

Measurement of Kerr constant and the non-resonant part of the static non-linear susceptibility χ(3)1212 (ω1,-ω1,o,o) in acetonitrile, benzaldehyde, acetophenone, acetone, ethyl methyl ketone, o-nitrotoluene, nitrobenzene, and benzoylchloride are reported. The variation of Kerr constant in nitrobenzene-benzene and o-nitrotoluene-benzene mixtures have also been experimentally determined for the first time for different molar fractions and compared with the theoretically obtained values using the mean field theory. The experimentally determined values of the dielectric constant(ε{lunate}) and the refractive index(n) have been used for the theoretical calculations. © 1991.

Journal	Physical Review A
ISSN	10502947
Open Access	No