Analysis of ground-state zero-field splitting for Mn2+ in hexagonal ZnS:Mn2+

The ground state splitting of d(5) configuration ion Mn2+ in ZnS:Mn2+ has been studied by diagonalizing the energy matrices for electron-electron repulsion, spin-orbit coupling and trigonal ligand field interactions. It is shown that in order to give a unified explanation for the EPR parameters a, D and (a - F) for Mn2+ in ZnS:Mn2+, a positive Dq has to be employed. This means that in tetrahedral ZnS the sulfur ion has a positive effective charge. This unusual result supports the Pauling's speculation that the sulfur ion in ZnS may be looked upon as an electron donor that forms a quadricovalent argon state of S2+ with sp(3) hybrid configuration. (C) 2003 Elsevier Ltd. All rights reserved.