Theoretical investigations of the electronic and magnetic structures for the [CoCl4]2− cluster in Cs3CoCl5 crystal

On the basis of the complete energy matrices for a d7 configuration ion in D2d symmetry ligand-field, the local structure parameter θ = 52.60° for [CoCl4]2− clusters in Cs3CoCl5 crystal is determined. It is shown that the ligand-field calculation results of θ are associated with the equivalent positions of the effective charges of chlorine ions, which are slightly different from the nuclear positions of chlorine ions θ0 = 53.0° ± 0.2° found by X-ray diffraction experiment. This difference means that there exists an obvious polarization effect for the electron clouds of chlorine ions in Cs3CoCl5 crystal. Furthermore, the theoretical g-factors and paramagnetic susceptibility are in agreement with the experimental findings.