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.