Matrix infrared study of O-initiated atomic oxidation of CH3Cl: Identification of the triplet CH3Cl center dot center dot center dot O complex

Infrared spectroscopic studies have been conducted on the products of the r eaction between atomic oxygen in its ground and excited states with normal and isotopically substituted methyl chloride in argon matrixes at 11 K. Wit h the O(D-1) atom, the major product is the hydrogen-bonded complex between formaldehyde and hydrogen chloride. Abstraction of a hydrogen atom from CH 3Cl by O(D-1) appears as a minor channel. Small amounts of HClCO were also found. Formation of CO-HCl as a secondary and primary product was observed. Reaction of CH3Cl with the O(P-3) atom was evidenced. Spectra suggest the formation of a collision complex CH3Cl ... O formed by addition of an oxyge n atom to CH3Cl. Ab initio calculations about the structure and vibrational spectrum of the CH3ClO singlet and CH3Cl ... O triplet are reported.