ArF laser photolysis of OCSe. I. Se(1<i>S</i>) quenching processes

Abstract

Quenching rates for Se(1S) and Se*2 by OCSe have been measured using ArF laser photolysis of OCSe at 193 nm for the generation of Se(1S) atoms and the reactive mechanism Se(1S)+OCSe→Se*2+ CO as the source of Se*2. The experimentally determined quenching rates are (1.6±0.4) ×10−10 and 4.6×10−11 cm3 molecule−1 sec−1 for the processes OCSe+Se(1S) and OCSe+Se*2, respectively. Evidence is presented which demonstrates that the Se*2 is formed initially in a state other than the strongly radiating B 3Σ−u level.