Bimolecular Reaction Dynamics of Thiophosgene with O(3P) Atoms

Abstract

The nascent vibrational and the near-nascent rotational state distributions for the SO(X3Σ-) product following the oxidation reaction of thiophosgene (CSCl2) with O(3P) have been studied by laser-induced fluorescence (LIF) spectroscopy on the (B3Σ-−X3Σ-) transition. O(3P) atoms are produced from the 355 nm photodissociation of NO2. The measured SO(X3Σ-) product vibrational state distribution can be characterized as Boltzmann with a vibrational temperature Tvib = 1150 ± 55 K corresponding to 8% of the available energy for the reaction. The statistical nature of the SO(X3Σ-) vibrational state distribution suggests a stable intermediate for this reaction, and ab initio calculations confirm a triplet dichlorosulfine (Cl2CSO(3A‘‘)) as a minimum on the excited triplet state potential energy surface. Statistical modeling of the observed SO(X3Σ-) vibrational state distribution results in an available energy E = 18 kcal/mol, which is 1.6 kcal/mol more than the exoergicity of this reaction. On the basis of ab initi...