Zero‐field splitting and the d–d transitions of Mn²⁺ on Ca(II) sites in Ca₅(PO₄)₃F

Abstract

Abstract On the basis of the crystal field theory the energy matrices of a d 5 ion in C s (or C 2 ) symmetry are derived, which are applicable to all orthorhombic and tetragonal symmetries. Using the perturbation theory the analytical expressions connecting the zero‐field splitting parameters with the crystal field parameters are obtained for a 6 S‐state ion in arbitrary symmetry. It is shown that the zero‐field splitting of Mn 2+ on Ca(II) sites in Ca 5 (PO 4 ) 3 F, possessing C s point symmetry, can be reasonably understood by the spin–orbit coupling mechanism, and that the d–d transitions can be interpreted well by the crystal field model proposed by Zhao et al.