Theoretical investigations of the local distortion and spectral properties for VO2+ in SiO2 Glass

Abstract

Abstract The local distortions and the spin Hamiltonian parameters g factors g ∥, g ⊥ and the hyperfine structure constants A ∥ and A ⊥ for isolated vanadyl ions VO2+ doped in SiO2 glass at 700°C are theoretically investigated from the perturbation formulas of these parameters for a 3d1 ion in tetragonally compressed octahedra. In these formulas, the relationships between local structure of VO2+ ions center and the tetragonal crystal field parameters are established. As a result, the distortion of the ligand octahedron is attributed to the strong axial crystal-fields associated with the short V4+–O2− bond due to the strong V=O bonding in the silica matrix. The theoretical spin Hamiltonian parameters obtained in this work show reasonable agreement with the experimental data.