Takehisa Konishi

XAFS and XPS studies on the enhancement of methane adsorption by NiO dispersed ACF with the relevance to structural change of NiO

A remarkable enhancement of methane adsorptivity of activated carbon fiber (ACF) with dispersion of ultra fine NiO particles was observed. The Ni K-edge X-ray adsorption near-edge structures (XANES) and extended X-ray adsorption fine structures (EXAFS) spectra of dispersed NiO on ACF elucidated that the dispersed NiO showing the most remarkable enhancement effect has a specific structure whose nearest-neighbor atomic distance of NiO is larger than that of powdered NiO. The X-ray photoelectron spectroscopy (XPS) spectra suggested that the electrons of the ligand valence band in the dispersed NiO are tightly bound than those of the powdered NiO.

Orthorhombic-to-monoclinic phase transition of Ta2NiSe5induced by the Bose-Einstein condensation of excitons

Using the band structure calculation and mean-field analysis of the derived three-chain Hubbard model with phonon degrees of freedom, we discuss the origin of the orthorhombic-to-monoclinic phase transition of the layered chalcogenide Ta

Switching of Conducting Planes by Partial Dimer Formation in IrTe 2

_2

K 2 Cr 8 O 16 predicted as a half-metallic ferromagnet: Scenario for a metal-insulator transition

NiSe

Electronic structure of the strongly hybridized ferromagnet CeFe_2

_5

Iodine L-edge XAFS study of linear polyiodide chains in amylose and -cyclodextrin

. We show that the Bose-Einstein condensation of excitonic electron-hole pairs cooperatively induces the instability of the phonon mode at momentum

Important Roles of Te 5p and Ir 5d Spin–Orbit Interactions on the Multi-band Electronic Structure of Triangular Lattice Superconductor Ir1−xPtxTe2

q\rightarrow 0

Te 5 p orbitals bring three-dimensional electronic structure to two-dimensional Ir 0.95 Pt 0.05 Te 2

in the quasi-one-dimensional Ta-NiSe-Ta chain, resulting in the structural phase transition of the system. The calculated single-particle spectra reproduce the deformation of the band structure observed in the angle-resolved photoemission spectroscopy experiment.

On the interface magnetism of thin oxidized Co films: orbital and spin moments

Single-crystal X-ray diffraction was employed to study the structural-electronic phase transition of IrTe2 at approximately 270 K. The low-temperature structure was found to be a triclinic (space group \(P\bar{1}\)) characterized by the partial formation of Ir2 dimers in the triangular lattice of IrTe2, resulting in a structural modulation with a wave vector of q = (1/5, 0, −1/5). First-principles band calculations demonstrate that tilted two-dimensional Fermi surfaces emerge in the triclinic phase, suggesting that switching of the conducting planes occurs from the basal plane of the trigonal IrTe2 to the tilted plane normal to q of the triclinic IrTe2.

X‐Ray Absorption Fine Structure Spectroscopy Study of Arsenate Adsorption on Schwertmannite

Based on the first-principles electronic structure calculations, we predict that a chromium oxide