title: Theoretical investigations of the EPR g factors and the local structure for Er3+ in BaWO4.
abstract: The electron paramagnetic resonance (EPR) parameters g factors g(parallel) and g(perpendicular) as well as the local structure for Er3+ in scheelite-type BaWO4 are theoretically investigated by using the perturbation formulas of the EPR parameters for a 4f11 ion under tetragonal symmetry. In these formulas, the contributions to the EPR parameters arising from the second-order perturbation terms and the admixture of different states are included. It is found that the impurity-ligand bonding angles (or the polar angles) related to the fourfold axis in the tetragonal Er3+ center are about 1.5 degrees smaller than those in pure crystal. The calculated EPR parameters are in agreement with the observed values. The validity of the results is discussed.
authors.affiliation: Department of Applied Physics, College of Physical Electronics, University of Electronic Science and Technology of China, Chengdu, PR China. wushaoyi@netease.com
authors.forename: Shao-Yi
authors.initials: SY
authors.lastname: Wu
authors.forename: Hui-Ning
authors.initials: HN
authors.lastname: Dong
mesh_terms: D017609:Barium Compounds / Q000737:chemistry*; D003460:Crystallization; D004578:Electron Spin Resonance Spectroscopy; D004871:Erbium / Q000737:chemistry*; D008903:Minerals / Q000737:chemistry; D015394:Molecular Structure; D010087:Oxides / Q000737:chemistry*
chemical_list: D017609:Barium Compounds; D008903:Minerals; D010087:Oxides; D004871:Erbium