Theoretical studies of the local structures and EPR parameters for various Rh(2+) centers in AgCl

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	Theoretical studies of the local structures and EPR parameters for various Rh(2+) centers in AgCl
	H. M. Zhang; S. Y. Wu; P. Xu; L. L. Li
	2010
发表期刊	Journal of Molecular Structure-Theochem
ISSN	0166-1280
卷号	953 期号:1-3 页码:157-162
摘要	The local structures and electron paramagnetic resonance (EPR) parameters (the g factors, the hyperfine structure constants and the superhyperfine parameters) for various Rh(2+) centers in AgCl are theoretically studied using the perturbation formulas of these parameters for a 4d(7) ion in tetragonally and orthorhombically distorted octahedra. These defects include the tetragonally and orthorhombically elongated centers at low temperatures (labeled as T(L) and O(L)) and the tetragonally compressed center at high temperature (labeled as T(H)). The centers T(L) and O(L) are attributed to the substitutional Rh(2+) on Ag(+) site, associated with none and one next nearest neighbour cation vacancy V(Ag) along [1 0 0] (or X) axis, respectively. The ligand octahedron in the orthorhombic center O(L) is found to suffer the relative elongation Delta Z(OL) approximate to 0.079 angstrom along [0 01] (or Z) axis due to the Jahn-Teller effect, and the intervening ligand Cl(-) in the V(Ag) and the Rh(2+) may experience the inward displacement Delta X approximate to 0.008 angstrom towards the central Rh2*. In the center T(L), the uncompensated [RhCl(6)](4-) cluster is found to suffer the relative elongation Delta Z(TL) approximate to 0.116 angstrom along [0 0 1] axis due to the Jahn-Teller effect. As for the center T(H), one V(Ag) occurs in the next nearest neighbour site along [0 0 1] axis, which may compel the intervening Cl(-) in the V(Ag) and the Rh(2+) to shift towards the central Rh(2+) by an amount Delta Z(H) approximate to 0.112 angstrom. In the calculations of the superhyperfine parameters, the related molecular orbital coefficients and the ligand unpaired spin densities are determined quantitatively from the cluster approach in a uniform way. The theoretical EPR parameters based on the above local structures show good agreement with the experimental data for all the centers. (C) 2010 Elsevier B.V. All rights reserved.
部门归属	[zhang, hua-ming; wu, shao-yi; xu, pei; li, li-li] univ elect sci & technol china, inst appl phys, chengdu 610054, peoples r china. [wu, shao-yi] chinese acad sci, int ctr mat phys, shenyang 110016, peoples r china.;wu, sy (reprint author), univ elect sci & technol china, inst appl phys, chengdu 610054, peoples r china;wushaoyi@netease.com
关键词	Crystal-fields And Spin Hamiltonians Electron Paramagnetic Resonance (Epr) Rh(2+) Agcl Transition-metal Ions Spin-hamiltonian Parameters Atomic Screening Constants Solution-grown Nacl Jahn-teller Ions Spectroscopic Investigations Paramagnetic Resonance Superposition Model Magnetic-resonance Crystal-field
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文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/31697
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	H. M. Zhang,S. Y. Wu,P. Xu,et al. Theoretical studies of the local structures and EPR parameters for various Rh(2+) centers in AgCl[J]. Journal of Molecular Structure-Theochem,2010,953(1-3):157-162.
APA	H. M. Zhang,S. Y. Wu,P. Xu,&L. L. Li.(2010).Theoretical studies of the local structures and EPR parameters for various Rh(2+) centers in AgCl.Journal of Molecular Structure-Theochem,953(1-3),157-162.
MLA	H. M. Zhang,et al."Theoretical studies of the local structures and EPR parameters for various Rh(2+) centers in AgCl".Journal of Molecular Structure-Theochem 953.1-3(2010):157-162.