Related papers: Combined first-principles and EXAFS study of struc…

Polarized infrared reflectivity spectra of a (110)-oriented TbScO3 single crystal plate were measured down to 10 K. The number of observed polar phonons active along the crystallographic c axis at low temperatures is much higher than…

The caged compound LaRu2Zn20 exhibits a structural transition at TS =150 K, whose driving mechanism remains elusive. We have investigated atomic dynamics by the measurements of specific heat C and inelastic X-ray scattering (IXS). The…

Zirconia (ZrO2) is an important material with technological applications which are affected by point defect physics. Ab-initio calculations are performed to understand the structural and electronic properties of oxygen vacancies and…

The molybdate oxides SrMoO$_3$, PbMoO$_3$, and LaMoO$_3$ are a class of metallic perovskites that exhibit interesting properties including high mobility, and unusual resistivity behavior. We use first-principles methods based on density…

A complete set of all optical phonon modes predicted by symmetry for bixbyite structure indium oxide is reported here from a combination of far-infrared and infrared spectroscopic ellipsometry, as well as first principle calculations.…

BaBiO3 is a well-known example of a 3D charge density wavecompound, in which the CDW behavior is induced by charge disproportionation at the Bi site. At ambient pressure, this compound is a charge-ordered insulator, but little is known…

The infrared (IR) reflectivity spectra of orthorhombic manganese perovskites PrMnO$_3$ and CaMnO$_3$ are studied in the frequency range of optical phonon modes at temperatures varying from 300 to 4 K. The IR phonon spectra of these two…

We perform first principles simulations for the structural, elastic and electronic properties of orthorhombic samarium orthoferrite $SmFeO_3$ within the framework of density functional theory. A number of different density functionals, such…

The {57}Fe-specific phonon density of states of Ba(Fe(1-x)Co(x))2As2 single crystals (x=0.0, 0.08) was measured at cryogenic temperatures and at high pressures with nuclear-resonant inelastic x-ray scattering. Measurements were conducted…

The perovskite ruthenates (ARuO3, A = Ca, Ba, or Sr) exhibit unique properties owing to a subtle interplay of crystal structure and electronic-spin degrees of freedom. Here, we demonstrate an intriguing continuous tuning of crystal symmetry…

First principles density functional theory (DFT) simulations of antiferroelectric (AFE) PbZrO$_3$ and PbHfO$_3$ reveal a dynamical instability in the phonon spectra of their purported low temperature $Pbam$ ground states. This instability…

A correlation between the crystal structure and magnetic properties of system (1-x)BiFeO$_3$-(x)BaTiO$_3$ with compounds across the morphotropic phase boundary was studied using X-ray and neutron diffraction, magnetometry, and Mossbauer…

We have investigated the electronic, vibrational, optical, thermal and piezoelectric properties of LiNbO$_3$, LiTaO$_3$ and Li$_2$NbTaO$_6$ using the first-principles calculation based on the density functional theory. It also shows…

X-ray absorption spectra of oxide systems Ba_{1-x}K_xBiO_3 and BaPbO_3 above Bi- and Pb-L3 absorption edges were investigated. It was shown that oxygen ions move in double-well potential and their oscillations are correlated with charge…

Perovskite solid solutions PbHfO3-PbSnO3 offer valuable opportunities for studying the formation mechsnisms of incommensurate phases, owing to the presence of an intermediate (between cubic and incommensurate) phase, which is stabilized in…

In the layered transition metal oxide LiNbO$_2$ the Nb$^{3+}$ ($4d^2$) ion is trigonal-prismatically coordinated with O ions, with the resulting crystal field leading to a single band system for low energy properties. A tight-binding…

The impact of ordered vacancies on the dynamic stability of perovskites is investigated under the $\textit{ab initio}$ framework with a focus on cubic BaFeO$_{3}$ ($Pm\bar{3}m$) and vacancy-ordered monoclinic BaFeO$_{2.67}$ ($P2_{1}/m$).…

We show that in YVO3 new hard phonons gradually become zone center active below ~210 K verifying that a lattice phase transition takes place at about that temperature. The Debye-Waller factor found from EXAFS measurements show an additional…

Crystal structure, electronic state of Ir$^{4+}$, and magnetic properties of the antifluorite compound K$_2$IrBr$_6$ are studied using high-resolution synchrotron x-ray diffraction, resonant inelastic x-ray scattering (RIXS), thermodynamic…

We present the single-crystalline x-ray diffraction study on the Ba4Ru3O10 consisting of the corner-shared Ru3O12 trimers. The crystal structure is re-determined from 78 to 300 K across an antiferromagnetic transition at 105 K. The…