Theoretical investigation of the local lattice structure of Mn 2+ ion doped in tetragonal K 2 ZnF 4 crystal

The complete energy matrices $\left( {252\times 252} \right)$ for a d 5configuration ion in a tetragonal ligand-field has been constructed on the basis of the complete set of basis $\left| {L,S,M_L ,M_S } \right\rangle$ of d 5configuration (252 dimension), and the relationship between the low-symmetry EPR parameters b 2 0 ,b 4 0 and the local distortion parameters has been established based on the complete energy matrices. As an application, we have studied the EPR parameters and the local lattice structure of Mn 2+ ion doped in tetragonal K 2ZnF 4 system. The calculation indicated that the local lattice structure around a tetragonal Mn 2+ ion center has an expansion distortion. Simultaneously, the local lattice structure parameters R 1 =2.0727 Å, R 2 =2.0801 Å at room temperature (295 K) and R 1 ′ =2.0439 Å, R 2 ′ =2.05478 Å at low temperature (4.2 K) are determined. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 200671.70.Ch Crystal and ligand fields, 76.30.-v Electron paramagnetic resonance and relaxation,