Related papers: Comparative study of ordered and disordered Y1-xSr…
Oxygen vacancy ordering in perovskite-type transition-metal oxides plays an important role in the emergence of exotic electronic properties, as typified by superconducting cuprates. In this study, we predict the stability of…
By means of single-crystal X-ray diffraction we have revealed the breaking of centrosymmetry when lowering the temperature under T$_s$ = 200 K concomitantly with the setting of a commensurate superstructure in the small A-site quadruple…
Solid matter is classified through symmetry of ordering phenomena. Experimentally, this approach is straightforward, except when distinct orderings occur with identical or almost identical symmetry breaking. Here we show that the cuprate…
The local atomic disorder and the electronic structure in the environment of manganese atoms in LaMnO_3 has been studied by x-ray absorption spectroscopy, over a temperature range (300K to 870K) covering the orbital ordering transition…
The crystal structure of a disordered form of Cr$_{1/3}$NbS$_2$ has been characterized using diffraction and inelastic scattering of synchrotron radiation. In contrast to the previously reported symmetry (P6$_3$22), the crystal can be…
Due to a large discrepancy between theory and experiment, the electronic character of crystalline boron carbide B$_{13}$C$_{2}$ has been a controversial topic in the field of icosahedral boron-rich solids. We demonstrate that this…
Using low-energy electron diffraction, we show that the room-temperature $(\sqrt{2}\times\sqrt{2})R45^\circ$ reconstruction of Fe$_3$O$_4$(100) reversibly disorders at $\sim$450 $^\circ$C. Short-range order persists above the transition,…
A theoretical description is presented for low-temperature magnetic-field induced three-dimensional (3D) ordering transitions in strongly anisotropic quantum antiferromagnets, consisting of weakly coupled antiferromagnetic spin-1/2 chains…
We report the synthesis and properties of two new insulating phases of SrFeO3-d with introduction of oxygen deficiencies in metallic SrFeO3 ; one with 0.15 < d < 0.19 (sample A)and the other above d = 0.19 (sample B). Sample A shows large…
Effects of Sr substitution at A-site in ordered perovskite Ba3-xSrxMnNb2O9 (x = 1 and 3) have been investigated using X-ray diffraction, magnetization, dielectric/magnetodielectric and neutron diffraction measurements. The parent compound…
In order to gain insight into suppression of the ferromagnetic ordering temperature, local studies utilizing 99,101Ru zero-field spin-echo NMR, along with complimentary magnetization, high-angle x-ray diffraction, and Ru K-edge XAFS…
Liquid electrolytes adsorbed at the surface of metallic electrodes display a multitude of structures that can largely differ from the parent bulk system, both in terms of composition and local organization. In particular, the existence of…
We report a x-ray resonant diffraction study of the perovskite Pr0.6Ca0.4MnO3. At the Mn K-edge, this technique is sensitive to details of the electronic structure of the Mn atoms. We discuss the resonant x-ray spectra measured above and…
We present the results of an LDA and LDA+U band structure study of the monoclinic and the corundum phases of V2O3 and argue that the most prominent (spin 1/2) models used to describe the semiconductor metal transition are not valid.…
We report ARPES studies combined with DFT+DMFT calculations to confirm that the magnetic ordering vector transition from \textbf{Q}=(1/2,0,0) to \textbf{Q}=(1/3,0,0) in the metallic triangular antiferromagnets Co$_{1/3\pm\epsilon}$TaS$_2$…
The structure of CO adsorbates on the Rh(110) surface is studied at full coverage using first-principles techniques. The relative energies of different adsorbate geometries are determined by means of accurate structure optimizations. In…
We have compared the ground-state energy of several observed or proposed " 2 \sqrt{2} x 2 \sqrt{2} oxygen (O) ordered superstructures " (from now on HS), with those of "chain superstructures" (CS) (in which the O atoms of the basal plane…
Compositionally tunable vanadium oxyhydrides Sr2VO4-xHx (x = 0 - 1) without considerable anion vacancy were synthesized by high-pressure solid state reaction. The crystal structures and their properties were characterized by powder neutron…
The crystal and magnetic structures of the specified CMR manganite system have been studied as a function of $y=(0.2-1)$ across the metal-insulator (MI) transition, and of the oxygen mass ($^{16}$O, $^{18}$O). We quantitatively show how the…
We present recent Monte Carlo results on surfaces of bcc-structured binary alloys which undergo an order-disorder phase transformation in the bulk. In particular, we discuss surface order and surface induced disorder at the bulk transition…