Spectroscopic and kinetic study of the gas-phase CS2Cl adduct

Time-resolved UV–vis absorption spectroscopy (TRUVVAS) has been coupled with 248 nm laser flash photolysis (LFP) of Cl2CO in the presence of CS2 (and in some cases O2, NO or NO2) to generate the CS2Cl radical adduct in the gas phase and study the spectroscopy and kinetics of this species. CS2Cl is found to possess a strong absorption band at λmax ≈ 365 nm with σmax = (2.3 ± 0.7) × 10−17 cm2 molecule−1 (base e) and a weaker band at λmax ≈ 480 nm; the gas-phase spectrum of CS2Cl is very similar to the previously reported liquid-phase spectrum in CCl4 solvent. Reaction of CS2Cl with O2 is found to be very slow; our data suggest that the rate coefficient for this reaction at 240 K is less than 5.0 × 10−18 cm3 molecule−1 s−1. Rate coefficients for CS2Cl reactions with CS2Cl (k3), NO (k5), and NO2 (k6) were measured at 240 K and, in units of 10−11 cm3 molecule−1 s−1, were found to be 2k3 = 15 ± 6, k5 = 2.2 ± 0.5, and k6 = 1.3 ± 0.4, where the uncertainties are estimates of accuracy at the 95% confidence level.