Abstract: Carbon tetrachloride was subjected to transient laser flash photolysis in the presence or absence of oxygen, transient absorption spectra were observed and analyzed. The experiment indicates that a series of micro-reactions occurred under 248 nm laser by a single photon absorption of CCl4, including the dissociation of the solvent and the formation of sophisticated substances－{CCl4－Cl}σ charge transfer complex,( CCl3＋…Cl－) ion pair and CCl3O2. These absorptions decay according to the first order kinetics, and the decay rate constants of {CCl4－Cl}σ charge transfer complex were obtained to be 3.38×106 s－1 and 3.65×106 s－1 in the presence and absence of oxygen, respectively, and its production has nothing to do with the oxygen. The decay rate constants of (CCl3＋…Cl－) were also gained to be 3.73×107 s－1 and 3.02×107 s－1 in the presence and absent of oxygen, respectively. However, CCl3O2 exists only in the presence of oxygen with a decay rate constant of 2.32×104 s－1.

Key words: Laser photolysis, Carbon tetrachloride, Flash, Transient substance, 　Free radical