Direct kinetic and mechanistic study of the OH/sup +/ dimethylsulfide reaction under atmospheric conditions

The authors employed a pulsed laser photolysis - pulsed laser induced fluorescence technique to carry out direct, real time studies of OH reactions with DMS and DMS-d/sub 6/ in N/sub 2/, air and O/sub 2/ buffer gases. Both temperature and pressure dependencies have been investigated. They find that the observed rate constant (K/sub obs/ identical to d(OH)/(OH)(DMS)dt) depends on the O/sub 2/ concentration. The results are consistent with a mechanism which includes an abstraction route, a reversible addition route, and an adduct + O/sub 2/ reaction which competes with adduct decomposition under atmospheric conditions.