Predissociation dynamics of the A2Σ+ state of SH radical: Fine-structure state distributions of the S(3PJ) products.

Photo-predissociation of rovibrational levels of SH (A²Σ⁺, v′ = 0–6) is studied using the high-n Rydberg atom time-of-flight technique. Spin–orbit branching fractions of the S(³P_J=2,1,0) products are measured in the product translational energy distributions. The SH A²Σ⁺v′ = 0 state predissociates predominantly via coupling to the ⁴Σ⁻ repulsive state. As the vibrational level v′ increases, predissociation dynamics change drastically, with all three repulsive states (⁴Σ⁻, ²Σ⁻, and ⁴Π) involved in the dissociation. Nonadiabatic interactions and quantum interferences among these dissociation pathways affect the fine-structure state distributions of the S(³P_J=2,1,0) products. [ABSTRACT FROM AUTHOR]