0000000000588226
AUTHOR
G. Vaitheeswaran
showing 3 related works from this author
Structural, vibrational, and electronic properties of TlReO4 studied using a first principles approach
2019
Present work provides extensive DFT study of TlReO4 using pseudopotential approach for understanding the structural and vibrational properties and full-potential linearized augmented plane wave method for electronic band structure and associated optical properties. Calculated bulk modulus value 29.77 GPa using LDA functional is found to be close to experimental value 26 GPa. The order of elastic constant along the principal axis clearly indicates the crucial role of Re and O3 atoms in the structural and mechanical properties of this material. Analysis of Born effective charge (BEC) along with gamma point phonon frequencies through density functional perturbation approach (DFPT) have also sh…
High-pressure structural, lattice dynamics, and electronic properties of beryllium aluminate studied from first-principles theory
2021
Abstract The present work reports the complete study of structural, vibrational, mechanical, and electronic properties of BeAl2O4 (known as Chrysoberyl) using first-principles computing methods. The calculated ground-state properties agree quite well with previous experiments. The computed phonon dispersion curves do not show imaginary frequencies confirming the dynamical stability. In addition, the calculated elastic constants also ensure the mechanical stability through fulfillment of mechanical stability criteria. Apart from that, the theoretically determined phonon frequencies agree quite well with previous Raman and infrared experiments at ambient conditions. Various thermodynamic prop…
Crystal structure and phase transition of TlReO4: a combined experimental and theoretical study
2020
Abstract The present work describes a density-functional theory (DFT) study of TlReO4 in combination with powder x-ray diffraction experiments as a function of temperature and Raman measurements at ambient temperature. X-ray diffraction measurements reveal three different structures as a function of temperature. A monoclinic structure (space group P21/c) is observed at room temperature while two isostructural tetragonal structures (space group I41/a) are found at low- and high-temperature. In order to complement the experimental results first-principles DFT calculations were performed to compute the structural energy differences. From the total energies it is evident that the monoclinic str…