Related papers: Prediction of Phase Transition in CaSiO$_3$ Perovs…
Barium zirconate BaZrO3 is one of few perovskites that is claimed to retain an average cubic structure down to 0K at ambient pressure, while being energetically very close to a tetragonal phase obtained by condensation of a soft phonon mode…
The highest pressure form of the major Earth-forming mantle silicate is MgSiO3 post-perovskite (PPv). Understanding the fate of PPv at TPa pressures is the first step for understanding the mineralogy of super-Earths-type exoplanets,…
Density-functional simulations are used to calculate structural properties and high-symmetry phonons of the hypothetical cubic phase, the stable orthorhombic phase and an intermediate tetragonal phase of magnesium silicate perovskite. We…
The primary phase of the Earth's lower mantle, (Al, Fe)-bearing bridgmanite, transitions to the postperovskite (PPv) phase at Earth's deep mantle conditions. Despite extensive experimental and ab initio investigations, there are still…
Low temperature properties of BaZrO3 are revealed by combining experimental techniques (X-ray diffraction, neutron scattering and dielectric measurements) with theoretical first-principles-based methods (total energy and linear response…
The structural phase transformation in the La2/3Ba1/3MnO3 perovskite manganite was studied by ultrasound, neutron diffraction and electron microscopy techniques. Minima of the velocity and maxima of the decrement of the ultrasound point out…
A topological insulating phase has theoretically been predicted for the thermodynamically unstable perovskite phase of YBiO$_{3}$. Here, it is shown that the crystal structure of the Y-Bi-O system can be controlled by using a BaBiO$_{3}$…
The 5d5 iridate CaIrO3 is isostructural with the post-perovskite phase of MgSiO3, recently shown to occur under extreme pressure in the lower Earth's mantle. It therefore serves as an analogue of post-perovskite MgSiO3 for a wide variety of…
The crystal structure of CH3NH3PbBr3 perovskite has been investigated under high-pressure by synchrotron-based powder X-ray diffraction. We found that after the previously reported phase transitions in CH3NH3PbBr3 (Pm-3m->Im-3->Pmn21),…
X-ray diffraction, dynamical mechanical analysis and infrared reflectivity studies revealed an antiferrodistortive phase transition in EuTiO3 ceramics. Near 300K the perovskite structure changes from cubic Pm-3m to tetragonal I4/mcm due to…
The hybrid halide perovskite CH3NH3PbI3 exhibits a complex structural behaviour, with successive transitions between orthorhombic, tetragonal and cubic polymorphs at ca. 165 K and 327 K. Herein we report first-principles lattice dynamics…
We have investigated the structural phase transitions of the transition metal oxide perovskites SrTiO$_{3}$, LaAlO$_{3}$ and LaTiO$_{3}$ using the screened hybrid density functional of Heyd, Scuseria and Ernzerhof (HSE06). We show that…
A previously unreported Pb-based perovskite PbMoO$_3$ is obtained by high-pressure and high-temperature synthesis. This material crystallizes in the $Pm\bar{3}m$ cubic structure at room temperature, making it distinct from typical Pb-based…
We present a revised atomistic picture of the order-disorder transition in the archetypal orbital-ordered perovskite material, LaMnO$_{3}$. Our study uses machine-learning-driven molecular-dynamics simulations which describe the temperature…
The composition of the lower mantle can be investigated by examining densities and seismic velocities of compositional models as functions of depth. In order to do this it is necessary to know the volumes and thermoelastic properties of the…
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…
The structure and ground state electronic structure of the recently synthesized SrPdO$_3$ perovskite [A. Galal {\em et al.}, J. Power Sources, {\bf 195}, 3806 (2010)] have been studied by means of screened hybrid functional and the GW…
The crystal structure of the layered, perovskite-related LaTiO_3.41 (La_5Ti_5O_{17+\delta}) has been studied by synchrotron powder x-ray diffraction under hydrostatic pressure up to 27 GPa (T = 295 K). The ambient-pressure phase was found…
We predict a new candidate high-temperature high-pressure structure of FeSiO$_3$ with space-group symmetry Cmmm by applying an evolutionary algorithm within DFT+U that we call post-perovskite II (PPv-II). An exhaustive search found no other…
BaTiO3 (BTO) is one of the most interesting classes of perovskite materials. The present study has been complied to explore some physical properties such as mechanical, vibrational, thermo-physical, and temperature dependent thermodynamic…