title: Communications: Photoinitiated bond dissociation of bromoiodomethane in solution: Comparison of one-photon and two-photon excitations and the formation of iso-CH(2)Br-I and iso-CH(2)I-Br.
abstract: Broadband UV-visible femtosecond transient absorption spectroscopy was used to monitor the excited state photochemistry of CH(2)BrI following one-photon excitation at 266 or 271 nm and two-photon excitation at 395 or 405 nm in 2-butanol. The results for one-photon excitation agree with earlier studies in acetonitrile, showing clear formation of iso-CH(2)Br-I following cleavage of the C-I bond. In contrast, two-photon excitation at 395 nm results in the appearance of a blueshifted photoproduct absorption band assigned to formation of iso-CH(2)I-Br following cleavage of the C-Br bond. The results are discussed in the context of prior experimental and theoretical work and the prospects for optical control of bond cleavage.
authors.affiliation: Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, Michigan 48109-1055, USA.
authors.forename: Kuo-Chun
authors.initials: KC
authors.lastname: Tang
authors.forename: Jian
authors.initials: J
authors.lastname: Peng
authors.forename: Kenneth G
authors.initials: KG
authors.lastname: Spears
authors.forename: Roseanne J
authors.initials: RJ
authors.lastname: Sension
mesh_terms: D006846:Hydrocarbons, Halogenated / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D010777:Photochemistry; D017785:Photons; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: D006846:Hydrocarbons, Halogenated; D012996:Solutions; C521928:bromoiodomethane; D008697:Methane