Lifetime saturation of SO2(3B1) molecules: evaluation of chemical and physical quenching channels in alkanes

摘要

Lifetime data at 25thinsp;deg;C for the decay of SO2(3B1) molecules have been obtained in the presence of high pressures of CH4, C2H6, and C3H8. At high pressures, the physical quenching channel saturates and a kinetic model which incorporates this effect has been applied to the SO2, alkane systems studied. This model permits one to evaluate the partitioning of the total quenching rate constants into their chemical and physical components. The value (in units of 103torrminus;1thinsp;sminus;1) of the chemical and physical quenching rate constants (zero pressure limit), respectively, are (0.18 and 4.70), (CH4); (1.66 and 7.70),(C2H6);and (12.5 and 6.5), (C3H8).