Infrared absorption of gaseous ClCS detected with time-resolved Fourier-transform spectroscopy

Abstract

A transient infrared absorption spectrum of gaseous ClCS was detected with a step-scan Fourier-transform spectrometer coupled with a multipass absorption cell. ClCS was produced upon irradiating a flowing mixture of Cl2CS and N-2 or CO2 with a KrF excimer laser at 248 nm. A transient band in the region of 1160-1220 cm(-1), which diminished on prolonged reaction, is assigned to the C-S stretching (nu(1)) mode of ClCS. Calculations with density-functional theory (B3P86 and B3LYP/aug-cc-pVTZ) predict the geometry, vibrational wave numbers, and rotational parameters of ClCS. The rotational contour of the spectrum of ClCS simulated based on predicted rotational parameters agrees satisfactorily with experimental observation; from spectral simulation, the band origin is determined to be at 1194.4 cm(-1). Reaction kinetics involving ClCS, CS, and CS2 are discussed. (C) 2007 American Institute of Physics.