Dipole moment Jahn-Teller effect

The cooperative Jahn-Teller effect (CJTE) as a viable mechanism of structural transformations in solids was mentioned for the first time in 1957 by Dunitz and Orgel [ 1 ] and McClure [2]. Relatively soon after that Kanamori [3] published a fundamental paper defining the basic approach to the problem. In 1966 Bersuker [4] suggested a Jahn-Teller model for formation an electric dipole moment of a molecule... 

In other cases there may be three equivalent minima of dipolar type on the adiabatic potential, e.g., in the cases of molecules with D3h symmetry. Such an adiabatic potential can be due to either the pseudo-Jahn-Teller effect or the Jahn-Teller effect in the case of twofold degenerate electronic terms with quadratic terms of the vibronic interactions included (the quadratic E (g) e problem). If the dipolar minima are deep enough and only the tunneling states are populated, then 7/Vibr and the operator of dipole moment can be expressed by matrices of the dimension 3x3 ... 

---