Excited electronic states, transition probabilities, and radiative lifetimes of CAs: a theoretical contribution and challenge to experimentalists

High-level CASSCF/MRCI calculations with a quintuple-ζ quality basis set are reported by characterizing for the first time a manifold of electronic states of the CAs radical yet to be investigated experimentally. Along with the potential energy curves and the associated spectroscopic constants, the dipole moment functions for selected electronic states as well as the transition dipole moment functions for the most relevant electronic transitions are also presented. Estimates of radiative transition probabilities and lifetimes complement this investigation, which also assesses the effect of spin-orbit interaction on the A (2)Π state. Whenever pertinent, comparisons of similarities and differences with the isovalent CN and CP radicals are made.