Investigation of Self-and Foreign Gas Collision-induced Transitions between M-resolved Rotational Levels of OCS

Four-level MW-MW double resonance experiments on rotational Stark levels j = 0, 1, 2 and 3 of OCS have been performed to investigate transfer of rotational energy by collisions of OCS with OCS, He, Ne, Ar, Kr, H2, N2, O2, and CH3F. Theoretical arguments are given for the interpretation of the experimentally determined η-values by considering Bloch-type equations of an "embedded" four-level system with ±M degeneracy of the energy levels. The results indicate significant deviations from first order dipole collisional interaction.