Antisymmetric resonant vibrational transition polarizabilities for even-electron molecules

Abstract

Under the adiabatic approximation, antisymmetric resonant vibrational transition polarizabilities for even-electron systems with the ground and excited vibronic states belonging to the real representations have been deduced to be zero by the time-reversal symmetry and group theory. Beyond the adiabatic approximation the non-adiabatic corrections to them are non-zero, particularly in the degenerate or near degenerate electronic states, such as Jahn–Teller and pseudo Jahn–Teller cases where adiabatic approximation breaks down. The results verify Buckingham’s conjecture of non-zero antisymmetric transition polarizabilities beyond the adiabatic approximation in 1988. The conclusions of this letter agree with the experiments of antisymmetric vibrational Raman scattering. The compact expressions for the non-resonant and resonant antisymmetric transition polarizabilities are given in the Appendix.