Abstract: The Photodissociation dynamics of C6H11Br was investigated near 234 nm. A two-dimensional photofragment ion-velocity imaging technique coupled with a (2+1) resonance-enhancedmultiphoton (REMPI) ionization scheme was utilized to obtain the angular and translational energy distributions of the nascent Br(2P3/2) and Br*(2P1/2) atoms. The relative quantum yields were obtained from (2+1) resonance-enhanced multiphoton ionization (REMPI) of the photofragment Br*(2P1/2) and Br(2P3/2). It was suggested that Br* came fromthe direct dissociation of S1 state mostly, while Br atom was produced by non-adiabatic transition between the S2 and T3 states. Consequently, the higher internal energy distribution and the broader translational energy distribution of Br channel than those of Br* formation channel can be explained well. The results indicated that a large fraction of the available energy translated into the internal energy of the fragments, which can be explained using the soft impulsive model. However, comparing with other long-chain bromoalkane, more available energy was translated into the kinetic energy. The relationship between the energy partition and the cyclohexyl radical structure were analyzed.

Key words: C6H11Br, Photodissociation dynamics, Velocity map ion imaging, REMPI