The crystal structure of RhSe2

Abstract

The crystal structure of RhSe 2 has been determined from X-ray powder diffraction data. RhSe2 has the pyrite-type structure (C2 of the Strukturbericht). A homogeneity range exists for the structure between about 60 and 71.4 atomic% selenium with a decrease in lattice constant with increasing selenilun content.

Strong Electron–Phonon Coupling Superconductivity Induced by a Low-Lying Phonon in IrGe

“…Considering that 5d compounds usually have smaller DOS at E F than 4d compounds due to their largely extended d-orbitals, the concurrent reduced DOS of IrGe and the enhancement of γ due to strong electron-phonon coupling may result in the comparable γ's for RhGe and IrGe. The detailed inspection of the single crystal and high resolution synchrotron powder diffraction data for RhGe and IrGe confirmed that both have the orthorhombic MnP-type structure with no long-range structural distortions, consistent with previous lower resolution studies 4,5) ; the structures refined from the single crystal data are presented in Table I. 13) The cell dimensions differ anisotropically on going from RhGe to IrGe, so the cell dimension changes are not simply a reflection of hard-sphere-like atomic sizes.…”

“…3) Several 4d and 5d-based transition-metal germanides MGe (M = Rh, Pd, Ir and Pt) crystallize in this structure type. [4][5][6] Superconducting T c 's of 0.96, 4.7 and 0.40 K have been reported for RhGe, IrGe and PtGe, respectively, and PdGe is not known to superconduct above 0.4 K. 7) The T c of 5d-based IrGe is exceptionally high among these isostructural compounds: five times that of RhGe, its 4d analog, and ten times that of the compound based on Pt, Ir's neighbor in the periodic table. This anomalous behavior suggests that a key factor might be present in IrGe that enhances its T c .…”

Refinement of the Crystal Structures of Palladium-rich In-Pd Compounds by X-Ray and Neutron Powder Diffraction

“…Our diffraction data confirm the structure type of Rh 5 Ge 3 [35], which may be described as a stuffed, distorted variety of the CoSn-type [36] or a distorted Pt 5 Ga 3 -type structure [37]. We provide crystal structure parameters of much better accuracy than reported previously.…”

Synthesis and Electrical Properties of (Pb,Bi)TiO3 Ceramics

“…In general, the density strongly depends on the compositions of the pellet samples, which was determined from their mass and volume. 35 The density values of the green as well as sintered pellets have been listed in Table I. The density of the PBT pellets before sintering was found to lie in the range from 3.43 to 3.79 g/cm 3 .…”