A theoretical study of the thermal decomposition of fluoromethanethiol (CH₂FSH)

Abstract

A potential energy surface for the unimolecular decomposition of fluoromethanethiol has been reported at the G2(MP2) level of theory. Eleven product channels of CH₂FSH were fully detailed. Five possible decomposition pathways of the CH₃SF isomer were also examined. The calculations reveal that the four-center 1,2-HF elimination mechanism rather than the bond scission mechanism dominates the decomposition of both CH₂FSH and CH₃SF. The rate coefficients of the formation of HF at the high-pressure limit were deduced. The enthalpies of formation (Δ_fH₀^° and Δ_fH₂₉₈^°) of thirteen sulfur-containing species involved in the CH₃SF system were predicted at the G2(MP2) level.

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