A theoretical spectroscopy study of the X³Σ⁻ and the A³Π states of the C₂S radical

Abstract

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.

Acknowledgements

This work was supported by the MIUR of Italy, the University of Bologna and the US Office of Naval Research (grant No. N00014-01-1-0235). Part of this work has been performed (by SC) under the Project HPC-EUROPA (R113-CT-2003-506079), with the support of the European Community—Research Infrastructure Action under the FP6 “Structuring the European Research Area” Programme. RT would like to acknowledge P. J. Knowles and H.-J. Werner for providing him with access to the MOLPRO code.