Fluorescence depletion spectroscopy of the CH/D–Ne B  2Σ−– X  2Π transition

Fluorescence depletion techniques were used to test vibronic and rotational assignments for the B 2Σ−–X 2Π transition of CH–Ne. Previous vibronic assignments [W. H. Basinger, U. Schnupf, and M. C. Heaven, Faraday Discuss. 97, 351 (1994)] were confirmed, and observations of transitions to dissociation continua provided accurate dissociation energies for the B and X states. Errors in the rotational assignments were discovered. Re analysis of the rotational structure yielded ground state parity splittings and improved rotational constants. Adiabatic model calculations were used to determine approximate angular potential energy curves for the B and X states. These calculations also accounted for the prominent optical activity of internal rotation in the spectrum.