Spontaneous Predissociation in I2

Abstract

Existing lifetime data for the B[O+u(3II)] state of I2 are discussed in terms of the radiative and predissociative decay components. Franck-Condon calculations for the B→ 1u(1Π) predissociation show that the lifetimes and photodissociation yields are consistent with the location of the 1u(1II) state deduced independently from absorption measurements. The predissociative decay rate is negligible near v′ = 14, rises to a sharp peak at v′∼5 and a broader, weaker maximum around v′ = 26. Rotational predissociation may be significant for absorption within ∼20 Å of the B-state dissociation limit.