Resonance raman investigation of the short-time dynamics of the ultraviolet photodissociation of bromoform

Abstract

We report ultraviolet resonance Raman spectra of bromoform (CHBr 3) in cyclohexane solution. The resonance Raman spectra show significant intensity in the overtones of the nominal Br-C-Br symmetric bend (ν 6), the nominal H-C-Br asymmetric bend (ν 3), the nominal Br-C-Br symmetric stretch (ν 2) and the nominal Br-C-Br asymmetric stretch (ν 5) vibrational modes suggesting that the short-time photodissociation dynamics have noticeable multidimensional character. The lack of strong combination bands between several of the Franck-Condon active modes suggests that more than one electronic transition contribute to the resonance Raman spectra. We briefly discuss the ultraviolet short-time photodissociation dynamics of bromoform and the potential implications for the secondary photodissociation reactions of the initially formed CHBr 2 radical.