COEXISTENCE OF JAHN-TELLER DISTORTIONS IN AN O-H SYMMETRY - A GENERAL VIEW INCLUDING THE SPIN-ORBIT INTERACTION

摘要

The coexistence of distortions of different symmetry due to the quadratic Jahn-Teller interactions in an octahedral complex is revisited. Analytical expressions for the position and energy of the different stationary points are given; afterwards the influence of the spin-orbit coupling is numerically evaluated for the overall system (T-3(1) + T-1(1)), which is encountered in the excited configuration of ns(2) impurities. An evaluation of the magnitude of the Jahn-Teller effect for 6-, 8-, and 12-coordinated complexes is performed according to the angular overlap model. Particular attention is paid to parameter values consistent with the eight-coordinated CsX:Tl+ systems (X = Cl, Pr, I). The coexistence of trigonal minima with tetragonal or orthorhombic ones is found for a rather wide range of parameter values with the minima better pronounced in the singlet state T-1 even for high values of the spin-orbit coupling. [References: 26]