Vibronic interaction effects constitute a new field of investigation in the physics and
chemistry of molecules and crystals that combines all the phenomena and laws originating …

This article reviews the polarizability model and its applications to ferroelectric perovskite
oxides. The motivation for the introduction of the model is discussed and nonlinear oxygen …

The phonon dispersion curves of the rutile-structure compounds GeO 2, SnO 2, NbO 2, and
VO 2 have been calculated in the framework of a shell model which had been used …

Specific heat measurements and theoretical calculations reveal an intimate analogy
between EuTiO 3 and SrTiO 3. For EuTiO 3, a hitherto unknown specific heat anomaly is …

The temperature dependence of infrared reflection spectra of single crystals of n-type
strontium titanate doped with 0.3 to 1.5 at.% niobium are reported from 10 to 5 000 cm− 1 in …

The equilibrium lattice parameters, bulk moduli, cohesive energies, k= 0 TO-phonon
frequencies and elastic constant C 44 of SnTe and PbTe are calculated completely from first …

A complete set of transverse and longitudinal phonon branches in each of the three principal
directions (< 100>,< 110>, and< 111>) and polarizations have been measured up to 60 meV …

The research in perovskite oxides is ever increasing since their discovery in 1945. The
number of compounds with this rather simple structure is growing continuously since then …

The frequency, temperature and wavevector dependence of the ferroelectric soft mode in
semiconducting SrTiO 3 was investigated by temperature derivative Raman spectroscopy …

The authors have calculated the phonon dispersion curves of barium titanate (BaTiO 3) in
the cubic phase. A nonlinear shell model is used, in which the fourth-order anharmonic core …