相关论文: Lattice dynamics of BaTiO3, PbTiO3 and PbZrO3: a c…
We investigate phonon transport in perovskite strontium titanate (SrTiO3) which is stable above its phase transition temperature (~105 K) by using first-principles molecular dynamics and anharmonic lattice dynamics. Unlike conventional…
The phonon dispersion curves of cubic BaTiO_3 have been computed within a first-principles approach and the results compared to the experimental data. The curves obtained are very similar to those reported for KNbO_3 by Yu and Krakauer…
Lead titanate (PbTiO3) is a classical example of a ferroelectric perovskite oxide illustrating a displacive phase transition accompanied by a softening of a symmetry-breaking mode. The underlying assumption justifying the soft-mode theory…
We present the vibrational properties and phonon dispersion for quasi-2D hybrid organic-inorganic perovskites (BA)$_2$CsPb$_2$I$_7$, (HA)$_2$CsPb$_2$I$_7$, (BA)$_2$(MA)Pb$_2$I$_7$, and (HA)$_2$(MA)Pb$_2$I$_7$ calculated from first…
Using first-principles calculations based on a variational density functional perturbation theory, we investigate the lattice dynamics of solid solutions of barium and strontium titanates. Averaging the information available for the related…
Phonons change remarkable the interatomic bond length in solids and this work suggest a novel method how this behavior can be displayed and analyzed. The bond-length spectrum is plotted for each of the different atomic bonding types. When…
The phonon spectra of calcium, strontium, barium, radium, cadmium, zinc, magnesium, germanium, tin, and lead titanates with the perovskite structure are calculated from first principles within the density functional theory. By analyzing the…
The lattice constants of Strontium titanate perovskite has been studied using the Density functional theory formalism at the PBE and the HSE levels of theory. The study has been done in all the 3 existing phases; namely cubic, orthorhombic…
We report the results of comprehensive study of the critical dynamics of the prototype perovskite antiferroelectric PbZrO$_3$. The combination of inelastic X-ray and diffuse X-ray scattering techniques and Brillouin light scattering was…
We report measurements of the phonon dispersion relations in non-superconducting, oxygen-deficient PrBa2Cu3O6+x (x ~ 0.2) by inelastic neutron scattering. The data are compared with a model of the lattice dynamics based on a common…
By means of first-principles calculations, various properties of SrRuO3 are investigated, focusing on its lattice dynamical properties. Despite having a Goldschmidt tolerance factor very close to 1, the phonon dispersion curves of the…
We report first principles density functional perturbation theory calculations and inelastic neutron scattering measurements of the phonon density of states, dispersion relations and electromechanical response of PbTiO3, BaTiO3 and SrTiO3.…
Structural phase transitions drive several unconventional phenomena including some illustrious ferroic attributes which are relevant for technological advancements. With this note, we have investigated the structural transition of…
We have determined the lattice dynamics of MgSiO$_3$ perovskite (bridgmanite) by a combination of single-crystal inelastic x-ray scattering and ab initio calculations. We observe a remarkable agreement between experiment and theory, and…
Barium zirconate (BaZrO$_3$) is one of the very few perovskites that is claimed to retain an average cubic structure down to \SI{0}{\K}, while being energetically very close to an antiferrodistortive phase obtained by condensation of a soft…
First-principles calculations were performed to investigate the ferroelectric properties of barium titanate and bismuth ferrite, as well as phonon dispersion of BaTiO3, using density functional theory and density functional perturbation…
A comparative study between PbTiO$_3$, PbZrO$_3$, and the solid solution PbZr$_{0.5}$Ti$_{0.5}$O$_3$ is performed on the soft mode lattice dynamics within the first Brillouin Zone. We consider the six unique B-site orderings for…
First-principles molecular dynamics simulations have been employed to analyze the proton diffusion in cubic BaZrO3 perovskite at 1300K, and a non-linear effect of an applied isometric strain of 2% on the lattice parameter has been observed.…
We report first principles calculations of the phonon dispersions of PbTe both for its observed structure and under compression. At the experimental lattice parameter we find a near instability of the optic branch at the zone center, in…
The phonon dispersion relations of crystal lattices can often be well-described with the harmonic approximation. However, when the potential energy landscape exhibits more anharmonicity, for instance, in case of a weakly bonded crystal or…