Comparative study of the Jahn-Teller effect in the 4T2g excited electron state of Cr3+ ion in elpasolite crystals

In the present paper, we report on a systematic comparative study of the dynamic 4T2g⊗eg Jahn-Teller effect for the Cr3+ ion in several elpasolite crystals (Cs2NaInCl6, Cs2NaYCl6, Cs2NaScCl6, Cs2NaYF6, Cs2NaYBr6, and K2NaScF6). Based on the available in the literature data on the frequencies of normal vibrations and Huang-Rhys parameters, we estimate the force constants, magnitudes of the normal modes displacements, changes in the chemical bond lengths and Jahn-Teller stabilization energy for all above mentioned systems. Several trends in the obtained results are revealed and analyzed.