title: Multiphoton dissociation dynamics of CH3Br.
abstract: The state-resolved photodissociation dynamics of CH3Br+ cations are studied using a combination of slice imaging and velocity mapping. Parent ions are prepared by (2 + 1) two-photon resonant three-photon ionization of CH3Br through the 5s Rydberg state in the energy region 29,069.8-29,976.0 cm(-1). Analysis of the photoelectron spectra reveals that CH3Br+ ions are produced in the spin-orbit ground electronic state with a wide distribution of vibrational excitation. The photodissociation of CH3Br+ produces CH3+ (X) + Br(2P(1/2))/Br(2P(3/2)) whose product state distribution shows substantial excitation in the umbrella mode of the CH3+ photofragment, especially when concurrently producing the Br(2P(1/2)) channel. The shapes of the photofragment angular distributions clearly show the different dissociation mechanisms in the Br(2P(1/2)) and Br(2P(3/2)) channels. The dissociation dynamics of the 5s Rydberg state of CH3Br are also presented and analyzed.
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023 Dalian, PRChina.
authors.forename: Fengyan
authors.initials: F
authors.lastname: Wang
authors.forename: M Laura
authors.initials: ML
authors.lastname: Lipciuc
authors.forename: Xueming
authors.initials: X
authors.lastname: Yang
authors.forename: Theofanis N
authors.initials: TN
authors.lastname: Kitsopoulos