Ham factors for a T×(τ2+ε) Jahn-Teller system at strong coupling

When an electronic triplet state interacts through a strong linear Jahn-Teller coupling with the five normal modes transforming as the tau 2 and epsilon representations of the cubic group, the potential energy minimum can be mapped onto a sphere in phase space. The additional effects of anharmonic coupling, quadratic Jahn-Teller coupling and unequal coupling to tau 2 and epsilon modes can all be represented by adding a potential energy that is a linear combination of the fourth- and sixth-order cubic invariant harmonic functions. Their effect can be pictured as a contour map on the spherical surface. The pattern of low-lying energy levels and the associated Ham factors have been worked out in this strong-coupling approximation. Some choices of the parameters give rise to potential surfaces with different dynamic properties from those previously studied.