An electrically discharged carbon disulfide-oxygen chemical laser

Since 1966 several lasing systems have been developed which are based on the oxidation of CS2. Regardless of experimental configuration, the pumping reaction is as follows: O + CS yields S + CO(+). A pulsed electrical discharge through mixtures at 3-5 torr (10-20 He: 3-5 O2: 0.2-0.3 CS2) initiated the reaction under flow conditions. Distribution peaked at v=13, in accord with observations of other laboratories, but also showed that substantial fractions were produced in the low v states. A comprehensive literature review was undertaken of C-S-O chemistry, and CO energy transfer processes. This material was assembled and inserted into a computer model. Tests of the model led to several conclusions: (1) eight reactions are sufficient to simulate the chemistry during the first 300 microsec after pulse initiation; (2) the reaction C + O2 yields O + CO may be partly responsible for the low level CO observed under high energy discharge conditions at 15 kV; (3) knowledge of the initial degrees of dissociation of the reactants is essential for accurate modeling; (4) temperature changes with time not only affect the overall chemistry, but particularly control the CO(+) relaxation; and (5) v-(v,T) rates play an important role in CO(+) relaxation, the most significant relaxers being O, O2, CS2, and OCS.