A theoretical application of coherent multicolor laser spectroscopy to selective control of singlet and triplet excitations in carbon monosulfide.

A theoretical proposal for preparation of chemically interesting coherent superpositions of molecular eigenstates using more than one laser was recently presented [T. A. Holme and J. S. Hutchinson, Chem. Phys. Lett. 124, 181 (1986)]. In this paper, the proposed coherent two-color excitation process is applied to the separation and selective control of excitations of singlet and triplet manifolds. The method is applied to diatomic CS, using experimentally derived vibronic states and spin-orbit couplings, and realistic laser intensities. We show that frequency tuning of two lasers can yield control of branching ratios between different excited triplet manifolds. We also generalize the previous two-laser proposal to multicolor excitations, and illustrate the extension with a three-laser highly selective excitation of a singlet vibronic state. [ABSTRACT FROM AUTHOR]