Affiliation:
1. College of Physics and Electronic Information, Shangrao Normal College , Shangrao , Jiangxi 334000 , China
2. Jiangxi Province Key Laboratory of Optoelectronic Information Science and Technology, Nanchang Hangkong University , Nanchang 330063 , Jiangxi , China
Abstract
Abstract
Local structures and electron paramagnetic resonance (EPR) parameters (g factors g
x
, g
y
, and g
z
) for the substitutional Ti3+ and W5+ centers in stishovite are theoretically investigated by using the high-order perturbation formulas of these parameters for a d1 ion in rhombically compressed octahedra. In the calculation formulas, the related molecular orbital coefficients are obtained from the cluster approach, and the relevant crystal-field (CF) parameters are determined from the superposition model, which enables to connect these CF parameters and, hence, the studied g factors with the local structures of the Ti3+ and W5+ centers in stishovite. Based on the calculations, the impurity–ligand bond lengths parallel and perpendicular to the C
2-axis are found to be R′|| (≈1.751 and 1.717 Å) and R′⊥ (≈1.788 and 1.806 Å) with the planar bond angles θ′ (≈89.0° and 88.2°) for the studied [TiO6]9− and [WO6]7− clusters, respectively. The calculated results are in good agreement with the experimental data, and the validity of the results is discussed.