Angular momentum constraints in radiationless processes: The symmetric top molecule

Abstract

The effects of rotational motion on the rate of intramolecular radiationless relaxation in polyatomic molecules is investigated in symmetric tops. The molecule is assumed to have the same symmetry in both the initial and final states so that vibration and rotational degrees of freedom remain separated during the relaxation. The effect of intermanifold Coriolis interaction on an internal conversion process between two singlet states is discussed in detail. The effect of Coriolis interaction on the intersystem crossing rate is also formulated; however a detailed calculation is not performed.