Trigonal ligand field and zero field splitting diagrams for the d5 configuration

Complete trigonal ligand field, Coulombic repulsion, and spin–orbit interaction matrices have been computed for the d5 configuration. The ligand field potential for D3d, D3, C3v and a special case of C3 symmetry is expressed as a normalized spherical harmonic (NSH) potential. Ligand field energy level diagrams for the quartet states, as well as zero field (spin–orbit) splitting diagrams for the 6A1(S) ground state of a six-coordinate system, are presented. The advantages and limitations of the NSH formulation are discussed. The sign of the zero field parameter D is correlated with the sense of the trigonal distortion for six coordinate d5 systems of D3d symmetry, and two manganese(II) systems characterized by D3d symmetry are specifically considered.