THE MOLECULAR AHARONOV-BOHM EFFECT IN BOUND-STATES BEYOND THE ADIABATIC APPROXIMATION

The linear E X epsilon Jahn-Teller model with an ''extrinsic'' Aharono v-Bohm solenoid of strength alpha, previously studied by Mead at the a diabatic level, is generalized to the vibronic case. Energies and eige nfunctions of the full vibronic Hamiltonian are calculated using eigen functions of a two-dimensional harmonic oscillator with the solenoid a dded at the origin. Oscillating spin densities and concomitant Ham's r eduction factors are evaluated. The neglect of the diagonal vector pot entials is equivalent to alpha=1/2 and, in this case, the reduction fa ctors vanish for vibronic angular momentum j=1/2. The symmetries of th e model are studied by partitioning technique. In the adiabatic regime , vibronic spectra with alpha=0 and 1/2 are compared to adiabatic calc ulations showing that the neglect of the diagonal vector potentials in fluences the spectra more than the adiabatic approximation. Finally, w ith alpha=1/2, degeneracies in the spectra show up at some vibronic co upling strengths, indicating a hidden dynamical symmetry.