A theoretical spectroscopy study of the X3Sigma- and the A3Pi states of the C2S radical

The spin-rovibronic levels for the X 3Σ−,A 3Π electronic system of C2S are calculated variationally, using ab initio potential energy surfaces and taking into account the non-adiabatic coupling between the two states. The energies of selected levels with Σ and Π vibronic symmetry, up to ∼16500cm−1, are reported and compared with available experimental data.