Ji Lei, Tang Ying, Zhu Rongshu, Wei Zhengrong, Zhang Bing
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China.
J Chem Phys. 2006 Oct 28;125(16):164307. doi: 10.1063/1.2360280.
The photodissociation dynamics of allyl bromide was investigated at 234, 265, and 267 nm. A two-dimensional photofragment ion velocity imaging technique coupled with a [2+1] resonance-enhanced multiphoton ionization scheme was utilized to obtain the angular and translational energy distributions of the nascent Br* (2P1/2) and Br (2P3/2) atoms. The Br fragments show a bimodal translational energy distribution, while the Br* fragments reveal one translational energy distribution. The vertical excited energies and the mixed electronic character of excited states were calculated at ab initio configuration interaction method. It is presumed that the high kinetic energy bromine atoms are attributed to the predissociation from 1(pipi*) or 1(pisigma*) state to the repulsive 1(nsigma*) state, and to the direct dissociation from 3(nsigma*) and 3(pisigma*) states, while the low kinetic energy bromine atoms stem from internal conversion from the lowest 3(pipi*) state to 3(pisigma*) state.
在234、265和267纳米波长下研究了烯丙基溴的光解离动力学。采用二维光碎片离子速度成像技术结合[2+1]共振增强多光子电离方案，获得了新生Br*（2P1/2）和Br（2P3/2）原子的角分布和平动能分布。Br碎片呈现双峰平动能分布，而Br碎片显示单峰平动能分布。利用从头算组态相互作用方法计算了垂直激发能和激发态的混合电子特性。推测高动能溴原子归因于从1（ππ）或1（πσ*）态预解离到排斥性的1（nσ*）态，以及从3（nσ*）和3（πσ*）态直接解离，而低动能溴原子则源于从最低的3（ππ*）态到3（πσ*）态的内转换。
