Studies of the spin-Hamiltonian parameters for Mo5+ ions in double molybdate Li2Zn2(MoO4)3 crystal annealed in a CO2 atmosphere

Abstract The spin-Hamiltonian parameters ( g factors g ∥ , g ⊥ and hyperfine structure constants A ∥ , A ⊥ ) of the tetragonal Mo 5+ center in double molybdate Li 2 Zn 2 (MoO 4 ) 3 crystal annealed in a CO 2 atmosphere are calculated from the high-order perturbation formulas based on the two-mechanism model. In these formulas, the contributions to spin-Hamiltonian parameters from both the crystal-field (CF) mechanism in the widely applied CF theory and the charge-transfer (CT) mechanism (which is neglected in CF theory) are included. The calculated results show reasonable agreement with the experimental values. The calculations indicate that the relative importance of CT mechanism is large and so the accurate and reasonable calculation of spin-Hamiltonian parameters for the high valence state d n ions in crystals should take the contributions from both the CF and CT mechanisms into account.