The density function perturbation theory (DFPT) is employed to study the linear thermal expansion and heat capacity at constant pressure (with the quasiharmonic approximation) for wurtzite GaN. The calculated results of linear thermal expansion coefficient and heat capacity at constant pressure...

The proton conductivity and the mobility arising from motions of the ionic and bonded defects, in hydrogen-bonded molecular systems are investigated by means of the quantum mechanical method. Our two component model goes beyond the usual classical harmonic interaction by inclusion of a quartic...

The dynamics of protons in hydrogen-bonded quasi one-dimensional networks are studied using a diatomic lattice model of protons and heavy ions including a φ<Superscript>4</Superscript> on-site substrate potential. It is shows that the model with linear and nonlinear coupling of the quartic type between lattice sites for...</superscript>

Near-normal incident infrared reflectivity spectra of a (001) YVO<Subscript>4</Subscript> single crystal have been measured at different temperatures in the frequency region between 100 and 6000 cm<Superscript>-1</Superscript>. The reflectivity spectra are analyzed with the factorized form of the dielectric function, and the dielectric...</superscript></subscript>

We have studied temperature evolution of the local as well as the average crystal structure of MgB<Subscript>2</Subscript> using real-space atomic pair distribution function (PDF) measured by high resolution neutron powder diffraction in a wide temperature range of T=10–600 K. We find small positive correlation...</subscript>