Examination of the electron paramagnetic resonance parameters and their pressure-induced shifts for the Mn2+ ion in Na2ZnCl4·3H2O

In order to overcome the difficulties, which arose in previous works, in explaining the electron paramagnetic resonance (EPR) parameters and their pressure-induced shifts for the Na2ZnCl4·3H2O:Mn2+ crystal, in this work exact complete energy diagonalization calculations were completed based on the analytical expressions for the EPR parameters of 3d5 ions in trigonal symmetry field proposed by Zhao. Results show that, in contrast with some authors, the local structure of Mn2+ in Na2ZnCl4·3H2O is C3v symmetry with four Cl− ligands instead of [MnCl3·H2O]−. The values of D and a and their pressure-induced shifts deduced are in good agreement with the experimental data.