Rovibronic levels of the CCN(X 2Π) radical

Abstract

The rovibronic levels in the electronic ground state X 2Π of the CCN radical have been calculated from three-dimensional potential energy functions obtained from a complete active space self-consistent treatment and semi-empirical adjustment. About twenty experimentally known rovibronic energy differences have been reproduced with an accuracy of 10 to 20 cm −1, and all existing J = P ( P ⩽ 7 2 ) levels up to 2500 cm −1 are reported. The electron-nuclear motion and anharmonic coupling effects have been analyzed.