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581.
Shinichirou Minemoto Kazutaka Takahashi Jun Matsumoto Masako Iseda Akira Terasaki Hideo Imoto Tamotsu Kondow 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):13-16
Optical absorption spectra of cobalt cluster ions, Co n + , and vanadium cluster ions, V n + , were analyzed by a theoretical calculation based on the spin-polarized DV-Xα method, and their electronic and geometric structures were obtained. Relative absorption cross section associated with each electronic transition was calculated; the calculation enables a qualitative comparison of calculated spectrum with a measured one not only in its transition energy but also in its intensity profile. This analysis shows that Co 4 + , Co 3 + , and V 4 + have, respectively, a tetrahedral structure with a bond distance of 2.00Å, an equilateral triangle with a bond distance of 2.30Å, and a distorted tetrahedral structure with five bonds having a distance of 2.34 Å and one of 2.89Å. The differences in the population between majority and minority spins (spin-difference) evaluated from the electronic structure thus obtained were 2.0, 1.7, and zero per atom in Co 3 + , Co 4 + , and V 4 + , respectively. These spin differences indicate a ferromagnetic and an antiferromagnetic spin-coupling in the cobalt and vanadium cluster ions, respectively. 相似文献
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Shinsaku Amano Dimitri Bogdanovski Hisanori Yamane Masami Terauchi Richard Dronskowski 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(5):1684-1689
For the Ti/O system, three titanium monoxide (TiO) phases (α, β, and γ) with defective NaCl‐type structures and a high‐temperature hexagonal phase (H) have been known for decades. In this work, single crystals of a novel polymorph, ɛ‐TiO, were synthesized by using a bismuth flux. X‐ray diffraction (XRD) revealed a hexagonal crystal structure (a=4.9936(3) Å, c=2.8773(2) Å, P 2m) that is isotypic with ɛ‐TaN. While the Ti atoms are surrounded by trigonal prismatic (sixfold coordination) and trigonal planar (threefold coordination) arrangements of O atoms, the O atoms are found in a pseudo‐square‐pyramidal arrangement of Ti atoms. First‐principles calculations of the formation enthalpy and the electron and phonon density of states and crystal orbital Hamilton population (COHP) analysis revealed that ɛ‐TiO is more stable than α‐TiO, which had previously been regarded as the most stable phase at low temperatures. 相似文献
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