Photolysis of bromotrichloromethane

Bromotrichloromethane vapour has been irradiated with light of 3650 Å wavelength. The photolysis to trichloromethyl radicals and bromine atoms, as evident from the formation of hexachloroethane, is both pressure and temperature dependent. The effect of the addition of inert gases on the quantum yield was also investigated. The results provide evidence for the existence of electronically excited bromotrichloromethane molecules and suggest that two exicted states may be involved. The data also provide information about the rate of abstraction of chlorine from bromotrichloromethane by trichloromethyl radicals: CCl₃·+CCl₃Br→^kbCCl ₄+CCl₂Br· k_b=(7.1±1.0) ×10⁶ exp (-10,500±800)/RT l. mole^-1 sec ^-1.