Theoretical studies of the dependence of EPR g-factors on local structure for the trigonal Er3+–VK centres in KMgF3 and KZnF3

The EPR parameters (zero-field splitting D and g factors g‖ and g⊥) and the local structure for the tetragonal Fe+ center in KTaO3 are theoretically studied by using the perturbation formulas of the EPR parameters for a 3d7 ion in tetragonally distorted dodecahedra. Based on these studies, we find that the impurity Fe+ may not locate on the regular dodecahedral K+ site but suffer a large off-center displacement ΔZ (≈ 0.43 Å) along one of the 100 〈or C4〉 axes, which is responsible for the large tetragonal distortion of the impurity center. The displacement ΔZ obtained in this work is comparable with that (≈ 0.46 Å ) of a similar monovalent Li+ on K+ site of KTaO3 obtained from the nuclear quadrupole shift and can be regarded as reasonable. The calculated g factors, particularly the anisotropy Δg (= Kg⊥ −g‖) based on the above displacement, agree with the observed values.

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Theoretical studies of the g factors and local structure for Cr5+ within Cr2O3 nanocrystals embedded in silica glass matrix

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2008.10.145 ◽

2009 ◽

Vol 477 (1-2) ◽

pp. 40-44 ◽

Cited By ~ 7

Author(s):

Shao-Yi Wu ◽

Li-Hua Wei ◽

Hui-Ning Dong ◽

Yue-Xia Hu ◽

Xue-Feng Wang

Keyword(s):

Local Structure ◽

Silica Glass ◽

Glass Matrix ◽

Theoretical Studies ◽

G Factors

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Theoretical studies of the g factors and local structure for the rhombic Fe+ center in NaF

Optik ◽

10.1016/j.ijleo.2014.07.032 ◽

2014 ◽

Vol 125 (19) ◽

pp. 5820-5824

Author(s):

Chang-Chun Ding ◽

Shao-Yi Wu ◽

Yong-Kun Cheng ◽

Min-Quan Kuang

Keyword(s):

Local Structure ◽

Theoretical Studies ◽

G Factors

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Investigation of the Spin Hamiltonian Parameters of Yb3+ in CaWO4 Crystal

Zeitschrift für Naturforschung A ◽

10.1515/zna-2004-1209 ◽

2004 ◽

Vol 59 (12) ◽

pp. 943-946 ◽

Cited By ~ 1

Author(s):

Hui-Ning Dong ◽

Shao-Yi Wu

Keyword(s):

Hyperfine Structure ◽

Local Structure ◽

Reasonable Agreement ◽

Second Order ◽

Order Perturbation ◽

Superposition Model ◽

Spin Hamiltonian ◽

Structure Constants ◽

Hamiltonian Parameters ◽

G Factors

In this paper, the spin Hamiltonian parameters g factors g∥ and g⊥ of Yb3+ and hyperfine structure constants A∥ and A⊥ of 171Yb3+ and 173Yb3+ in CaWO4 crystal are calculated from the two-order perturbation formulae. In these formulae, the contributions of the covalence effects, the admixture between J =7/2 and J =5/2 states as well as the second-order perturbation are included. The needed crystal parameters are obtained from the superposition model and the local structure of the studied system. The calculated results are in reasonable agreement with the observed values. The results are discussed.

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