Photochemistry of CS2/Cl complexes—combined pulse radiolysis–laser flash photolysis studies

Abstract

Complexes of chlorine atoms with carbon disulfide (CS 2 ) were produced by pulse radiolysis of CS 2 in halocarbons and photochemical reactions were studied by laser flash photolysis. Excitation of CS 2 /Cl complexes was resulted in rapid and permanent photobleaching. The photobleaching of CS 2 /Cl complexes is due to intermolecular chlorine atom abstraction in CCl 4 with a quantum yield of 0.04, while it is ascribed to hydrogen atom abstraction in 1,2-dichloroethane with a quantum yield of 0.21. The effects of additives were discussed based on the bond dissociation energy.

Solvent effects on the photochemistry of dimethyl sulfoxide–Cl complexes studied by combined pulse radiolysis and laser flash photolysis

“…The laser photolysis was carried out from the opposite side of the electron beam with a third harmonic pulse (355 nm, 6 ns duration) from an Nd:YAG laser (Quanta-Ray, DCR-11). Dosimetry and actinometry have been described before (Sumiyoshi et al, 2005b). All experiments were carried out at room temperature (16 ± 2 ℃ ).…”

“…Photochemical studies of benzene _ Cl π-complexes (Wu et al, 1996(Wu et al, , 1997 and CS 2 _ Cl σ-complexes (Sumiyoshi et al, 2005b) have shown that the reactivity of excited CS 2 _ Cl complexes is much higher than that of excited benzene _ Cl and substituted benzene _ Cl complexes, opposite to the reactivities of their ground states, where the reactivity of CS 2 _ Cl complexes is much lower than that of benzene _ Cl complexes (Sumiyoshi et al, 2005a). Since DMSO _ Cl complexes are the much less reactive (Sumiyoshi and Katayama, 1990a;Kumar and Neta, 1992) among these chlorine atom complexes, a much higher reactivity in photolysis can be expected.…”

Formation and photochemistry of organic sulfur compound–chlorine atom complexes

“…The laser flash photolysis was conducted with a third harmonic pulse (355 nm, 6 ns width) from an Nd:YAG laser (Quanta-Ray, DCR-11). Dosimetry and actinometry have been described in elsewhere (Sumiyoshi et al, 2006b). All experiments were carried out at room temperature (16 ± 2℃).…”

Theoretical Interpretation of the UV−vis Spectrum of the CS2/Cl Complex in the Spectral Region 320−550 nm

“…The experimental ultraviolet-visible (UV-vis) spectra of the CS 2 /Cl complex were observed in the gas and liquid phases. [12][13][14] The UV-vis spectrum of gaseous CS 2 /Cl shows an intense absorption around 365 nm with a cross section of (2.3 ( 0.7) × 10 -17 cm 2 molecule -1 and a weak broad band with a maximum near 480 nm. 12 A similar spectrum was also recorded upon UV irradiation 13 and pulse radiolysis 14 of a CCl 4 solution containing CS 2 .…”

“…[12][13][14] The UV-vis spectrum of gaseous CS 2 /Cl shows an intense absorption around 365 nm with a cross section of (2.3 ( 0.7) × 10 -17 cm 2 molecule -1 and a weak broad band with a maximum near 480 nm. 12 A similar spectrum was also recorded upon UV irradiation 13 and pulse radiolysis 14 of a CCl 4 solution containing CS 2 . The structure of CS 2 /Cl responsible for this absorption could not be positively identified based on the observed UV-vis spectrum.…”