ANTISYMMETRIC NONRESONANT VIBRATIONAL RAMAN-SCATTERING

Antisymmetric nonresonant vibrational Raman scattering is studied by using group theory, especially a time-reversal symmetry. The results show that under the Born-Oppenheimer (BO) approximation, the antisymmetric transition polarizabilities of even-electron systems are approximately 10(-4) times as large as symmetric ones, but beyond the Born-Oppenheimer approximation they are 10(-2) times as large as symmetric transition polarizabilities. For odd-electron systems under the BO approximation, the antisymmetric transition polarizabilities can be nonzero due to time-reversal symmetry. The results verify Buckingham's conjecture of nonzero antisymmetric transition polarizabilities beyond the BO approximation.