Related papers: Pressure-Induced Volume Collapse and Metallization…
X-ray diffraction studies to ~90 GPa at room temperature show that Fe$_{2}$TiO$_{4}$ ferrous inverse spinel undergoes the following sequence of structural transitions : cubic (Fd3m) to tetragonal (I41/amd)to orthorhombic(Cmcm) to…
The metal-insulator and spin state transitions of CoO under high pressure are studied by using density functional theory combined with dynamical mean-field theory. Our calculations predict that the metal-insulator transition in CoO is a…
TiPO$_4$ shows interesting structural and magnetic properties as temperature and pressure are varied, such as a spin-Peierls phase transition and the development of incommensurate modulations of the lattice. Recently, high pressure…
The phase stability of the MgMn2O4 spinel has been studied by means of high-pressure X-ray diffraction for pressures up to 30 GPa. Two samples with different inversion degrees have been considered. Both spinels undergo a phase transition…
In the present work, we report a detailed density functional theory calculation on polymorphic InVO$_4$ phases by means of projector augmented wave method. The computed first-order structural phase transformation from orthorhombic…
We employ a combination of the \emph{ab initio} band structure methods and dynamical mean-field theory to determine the electronic structure and phase stability of paramagnetic FeO at high pressure and temperature. Our results reveal a…
A pressure-induced phase transition, associated with an increase of the coordination number of In and Ta, is detected beyond 13 GPa in InTaO4 by combining synchrotron x-ray diffraction and Raman measurements in a diamond anvil cell with…
X-ray diffraction pressure studies at room temperature demonstrate that the spinel FeAl$_{2}$O$_{4}$ transforms to a tetragonal phase at ~18 GPa. This tetragonal phase has a highly irregular unit-cell volume versus pressure dependence up to…
The inversion and volume effects on magnetism in a spinel-type magnetically frustrated compound, CoAl2O4, and its gallium-substituted system, CoAl2-xGaxO4, were investigated. Magnetically frustrated Co2+ with spin S = 3/2 on the tetrahedral…
The electronic property and magnetic susceptibility of Ce$_3$Pd$_3$Bi$_4$ were systemically investigated from 18 K to 290 K for varying values of cell-volume using dynamic mean-field theory coupled with density functional theory. By…
We investigate the effect of pressure on the electronic and magnetic states of CdV$_2$O$_4$ by using ab initio electronic structure calculations. The Coulomb correlation and spin-orbit coupling play important role in deciding the…
We investigate the crystal structure and lattice vibrations of Sr$_2$IrO$_4$ by a combined phonon Raman scattering and x-ray powder diffraction experiment under pressures up to $66$ GPa and room temperature. Density functional theory (DFT)…
At room temperature, the normal oxide spinels NiCr_2O_4 and CuCr_2O_4 are tetragonally distorted and crystallize in the I4_1/amd space group due to cooperative Jahn-Teller ordering driven by the orbital degeneracy of tetrahedral Ni$^{2+}$…
We study the structural evolution of Sr$_3$Ir$_2$O$_7$ as a function of pressure using x-ray diffraction. At a pressure of 54 GPa at room temperature, we observe a first-order structural phase transition, associated with a change from…
Electronic structure calculations on the low dimensional spin-1/2 compound TiOCl were performed at several pressures in the orthorhombic phase, finding that the structure is quasi-one-dimensional. The Ti3+ (d1) ions have one t2g orbital…
The 5d-transition metal pyrochlore oxide Cd2Re2O7, which was recently suggested to be a prototype of the spin-orbit-coupled metal [Phys. Rev. Lett. 115, 026401 (2015)], exhibits an inversion-symmetry breaking (ISB) transition at 200 K and a…
The magnetic-field and temperature dependencies of ultrasound propagation and magnetization of single-crystalline CoCr2O4 have been studied in static and pulsed magnetic fields up to 14 T and 62 T, respectively. Distinct anomalies with…
The Local Density Approximation combined with Dynamical Mean-Field Theory (LDA+DMFT method) is applied to the study of the paramagnetic and magnetically ordered phases of hematite Fe$_2$O$_3$ as a function of volume. As the volume is…
The optical absorption of CdWO$_4$ is reported at high pressures up to 23 GPa. The onset of a phase transition was detected at 19.5 GPa, in good agreement with a previous Raman spectroscopy study. The crystal structure of the high-pressure…
Using configuration-state-constrained electronic structure calculations based on the generalized gradient approximation plus Hubbard U method, we sought the origin of the giant tetragonal ferroelectric distortion in the ambient phase of the…