Related papers: Post-Cotunnite phase of TeO2

We report neutron powder diffraction measurements on a series of NaxCoO2 samples with x near 0.75 which were prepared under different synthesis conditions. Two different crystal structures for the samples are observed at room temperature.…

The quantum O(2) model in 2+1 dimensions is studied by simulating the 3d O(2) model near criticality. Finite densities are introduced by a non-zero chemical potential mu, and the worm algorithm is used to circumvent the sign problem. The…

Quantum nuclear zero-point motions in solid H$_2$ and D$_2$ under pressure are investigated at 80 K up to 160 GPa by first-principles path-integral molecular dynamics calculations. Molecular orientations are well-defined in phase II of…

We measure diffusion coefficients in the lamellar phase of the nonionic binary system C$_{12}$EO$_6$/H$_2$O using fluorescence recovery after photobleaching. The diffusion coefficient across the lamellae shows an abrupt increase upon…

CaFe2As2 exhibits collapsed tetragonal (cT) structure and varied exotic behavior under pressure at low temperatures that led to debate on linking the structural changes to its exceptional electronic properties like superconductivity,…

We perform first-principles calculations of electronic structure and optical properties for UO2 and PuO2 based on the density functional theory using the generalized gradient approximation (GGA)+\emph{U} scheme. The main features in…

Results of X-ray diffraction experiments on solid oxygen at low temperature and at pressures up to 10 GPa are presented.A careful sample preparation and annealing around 240 K allowed to obtain very good diffraction patterns in the…

Far from being conclusively understood, the reactive interaction of water with rutile does still present a challenge to atomistic modelling techniques rooted on quantum mechanics. We show that static geometries of stoichiometric…

A displacive, 2nd order structural phase transition at Ts=395 K from space group I`4 2 m below Ts to I 4/m c m above Ts has been discovered in the two-dimensional spin dimer compound SrCu2(BO3)2. The temperature evolution of the structure…

We investigate the critical endpoints of the (3+1)-dimensional $Z_2$ gauge-Higgs model at finite density together with the (2+1)-dimensional one at zero density as a benchmark using the tensor renormalization group method. We focus on the…

We find that conjugated polymers can undergo reversible structural phase transitions during electrochemical oxidation and ion injection. We study poly[2,5-bis(thiophenyl)-1,4-bis(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)benzene] (PB2T-TEG), a…

We present for the first time the band structure calculation of $Bi_2Sr_2Ca_2Cu_3O_{10}$ compound in the tetragonal structure (space group $I4/mmm$). We used the Local Density Approximation (LDA) as in the Wien2k code. We analyze in detail…

In this work, we present a characterization of phase configuration in water-saturated sintered glass bead samples after oil injection, through the analysis of time-dependent diffusion coefficients obtained from sets of one-dimensional…

First-principles density functional theory calculations were carried out to determine the low energy geometries of anatase TiO$_2$(001) with Pt implants in the sublayers as substitutional and interstitial impurities as well as on the…

We calculate thermodynamic potentials and their derivatives for the three-dimensional $O(2)$ model using tensor-network methods to investigate the well-known second-order phase transition. We also consider the model at non-zero chemical…

To date, there has been no evidence for the macroscopic structural phase transition to the low temperature tetragonal structure (LTT) with a space group P42/ncm in high-TC cuprate of rare earth-free La2-xSrxCuO4 (LSCO). By investigating…

We use a combination of conventional density functional theory (DFT) and post-DFT methods, including the local density approximation plus Hubbard $U$ (LDA+$U$), PBE0, and self-consistent $GW$ to study the electronic properties of…

Synchrotron X-ray diffraction patterns were measured and analyzed for a polycrystalline sample of the room-temperature ferromagnet Sr3.12Er0.88Co4O10.5 from 300 to 650 K, from which two structural phase transitions were found to occur…

A structural transition at $T\approx 322$ K from the $Pmmm$ to $Pmma$ phase is found to coincide with an anomaly of resistivity. Another structural phase transition doubling the lattice parameter $c$, which has been postulated earlier to…

While the tetragonal antiferro-electrically distorted (AFD) phase with space group $I4/mcm$ is well known for SrTiO$_3$ to occur below 105 K, there are also some hints in literature of an orthorhombic phase, either at lower temperature at…