Comparative study of the energy levels structure of Cr³⁺: MIn(WO₄)₂ with M=Na, K, Rb

The crystal field parameters and the energy level structure of Cr ³⁺ ion are calculated in the exchange charge model of crystal field using the actual symmetry of the chromium positions. The trivalent chromium ion replaces the In cation in each host matrix and occupies the low site symmetry The calculated energy level schemes for each crystal are compared with each other and with experimental results. The obtained results are in good agreement with experimental data. Covalent effects were shown to play an important role in all considered crystals.