Showing papers by "V. R. K. Murthy published in 2014"
TL;DR: In this paper, the structural, optical and microwave dielectric properties of Ca1−xSrxMoO4 (x = 0.0, 0.2, 0.4, 0., 0.8 and 1.0) compositions were studied with help of Rietveld refinement and Raman spectroscopy measurements.
50 citations
TL;DR: In this article, the polarization response in polycrystalline Ni 0.9−y Cu y Zn 0.1 Fe 1.98 O 4−δ (y ǫ = 0, 0.2, 1.3, 0, 4, 0., 0.5) ferrite synthesized by solid-state reaction method was investigated.
36 citations
TL;DR: In this paper, a polycrystalline Ni 0.9− y Cu y Zn 0.1 Fe 1.98 O 4− δ powder was synthesized by conventional solid-state reaction method and X-ray diffraction analysis confirmed single phase cubic spinel phase formation in the calcined powders.
12 citations
TL;DR: The stability of phase transition temperatures and textural changes for thermotropic pure and nanodoped --alkyloxybenzoic acid mesogens were aimed to study at considerable time periods.
Abstract: The stability of phase transition temperatures and textural changes for thermotropic pure and nanodoped --alkyloxybenzoic acid mesogens were aimed to study at considerable time periods Frequency and temperature dependent dielectric constant and dielectric loss for the pure and nanodoped liquid crystals were carried out Significant anomalies in dielectric studies were observed near phase transitions when dielectric constant and dielectric loss had been measured as a function of temperature and frequency Changes in dielectric constant and loss were observed and there were no apparent changes at high frequencies instead maintaining constant values The variations in conductivity, activation energy, and relaxation times had also been studied in the nematic and smectic phases The temperature dependent dielectric constant stability (temperature coefficient of dielectric constant ) had shown shift in the observed frequency range of thermotropic liquid crystals corresponding to the change in the dielectric constant values
3 citations
Journal Article•
TL;DR: In this article, the frequency dependent complex dielectric permittivity was determined by using the open-ended coaxial probe technique method in the microwave frequency range from 20MHz-20 GHz.
Abstract: The molecular interaction between the polar systems of isobutanol and methyl benzoate for various mole fractions at different temperatures were studied by determining the frequency dependent complex dielectric permittivity by using the open-ended coaxial probe technique method in the microwave frequency range from 20MHz-20 GHz. The geometries are optimized at HF, B3LYP with 6-311G and 6-311G+ basis sets. Dipole moments of the binary mixtures are calculated from the dielectric data using Higasi’s method and compared with the theoretical results. Conformational analysis of the formation of hydrogen bond between isobutanol and methyl benzoate is supported by the FT-IR, 1NMR and molecular polarizability calculations. The average relaxation times are calculated from their respective Debye and Cole-Cole plots. The activation entropy, activation enthalpy, Gibbs free energy of activation and Kirkwood correlation ‘g’ factor, excess permittivity (ε), excess inverse relaxation time (1/τ) , Bruggeman parameter (fB) have also been determined for isobutanol and methyl benzoate and the results were correlated. Keywords— Complex dielectric permittivity; relaxation time; excess dielectric and thermodynamic parameters; ab-initio calculations.
2 citations