Trichloroacetyl chloride, CCl3COCl, as an alternative Cl atom precursor for laboratory use and determination of Cl atom rate coefficients for n-CH2CH(CH2)xCN (x = 3–4)

Abstract

An investigation of CCl₃COCl was conducted with the purpose of using the compound as an alternative Cl atom precursor in laboratory settings. CCl₃COCl can be used with or without O₂ as a source of Cl atoms and photolysis studies in air and N₂ diluent displayed COCl₂ and CO as being the major photolysis products. Relative rate studies were performed to determine the Cl atom rate coefficients for reaction with CH₃Cl and C₂H₂ and the results were in agreement with literature values. Cl atom rate coefficients for reaction with n-CH₂CH(CH₂)₃CN and n-CH₂CH(CH₂)₄CN were determined as (2.95 ± 0.58) × 10⁻¹⁰ and (3.73 ± 0.60) × 10⁻¹⁰ cm³ molecule⁻¹ s⁻¹, respectively. CCl₃COCl requires UV-C irradiation, so not all molecules are feasible for use in e.g. relative rate studies. Furthermore, it is recommended to perform experiments with O₂ present, as this minimizes IR feature disturbance from product formation.