Dynamics of the B ³Π(0u+) and A ³Π(1u) States of Chlorine by Laser Induced Fluorescence

Abstract

Chlorine B ³Π(0u+) state lifetimes have been measured by laser-induced fluorescence in several predissociated (υ′ = 14–19,21) and non-predissociated (υ′ = 5–12) levels. Trial and error Franck-Condon calculations have been performed to check the nature and position of the predissociating state. The results have been used to give a value of Re for the A ³Π(1u) state responsible for predissociation, Re = 2.48 ± 0.01 Å. The obtained data show that interference effects due to crossing between B and A states modify the lifetimes of the B state appreciably. The inadequacy of the low-lying vibrational levels region, i.e. υ′ < 8, to measure the radiative lifetime of the B state (τR(B)) is shown. Previous values for τR(B) can therefore be affected by considerable errors.