Lifetimes of the A 1Π and low-lying triplet states of CO

Abstract

The available experimental data concerning the lifetimes of the A 1Π, a′ 3Σ +, e 3Σ − and d 3Δ is reassessed in the light of a recently completed perturbation analysis of the ν=0–4 levels of the A 1Π state of CO. This work provides an extensive set of spin-orbit and rotation-electronic parameters characterizing the interactions of the A 1Π state with adjacent triplet and singlet states. Some of the resulting mixing coefficients are used to analyze the available lifetime measurements both of short-lived levels, of essentially 1Π character, and long-lived triplet levels. In several cases, the intrinsic lifetimes of the A 1Π (ν) and of the perturbing triplet state are determined. The strong J dependence of lifetimes are perfectly reproduced by the model and predictions are made for yet unmeasured levels.