Photofragment translational spectroscopy of ICl near 304 and 280 nm: Observation of an intense hot band effect  

作　　者：CHENG Min YU ZiJun XU XiLing YU Dan DU YiKui ZHU QiHe 

机构地区：[1]Beijing National Laboratory of Molecular Sciences,State Key Laboratory of Molecular Reaction Dynamics,Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China

出　　处：《Science China Chemistry》2012年第6期1148-1154,共7页中国科学(化学英文版)

基　　金：supported by the National Natural Science Foundation of China (20433080)

摘　　要：The photodissociation dynamics of IC1 has been studied near 304 and 280 nm on a simple miniature time of flight (mini-TOF) photofragment translational spectrometer with a short pulse of a weak acceleration field. An intense hot band effect was ob- served. Many small peaks were resolved in each photofragment translational spectrum (PTS). Based on simulations, the principal peaks were assigned not only to the different photodissociation channels (1) I + C1, (2) I + CI*, (3) I* + C1, or (4) I* + CI*, but also to the different chlorine isotopes (35C1 and 37C1). Moreover, some extra peaks showed the existence of an intense hot band effect from vibrationally excited ICI molecules, though only a few percent of ICI molecules remained in the vibrationally excited states in our supersonic molecular beam. Based on the spectra near 304nm, the quantum yield Φ of each channel, the curve crossing, and the branching fraction a from each transition state were determined.The photodissociation dynamics of ICl has been studied near 304 and 280 nm on a simple miniature time of flight (mini-TOF) photofragment translational spectrometer with a short pulse of a weak acceleration field. An intense hot band effect was observed. Many small peaks were resolved in each photofragment translational spectrum (PTS). Based on simulations, the principal peaks were assigned not only to the different photodissociation channels (1) I + Cl, (2) I + Cl*, (3) I* + Cl, or (4) I* + Cl*, but also to the different chlorine isotopes (35Cl and Cl). Moreover, some extra peaks showed the existence of an intense hot 37 band effect from vibrationally excited ICl molecules, though only a few percent of ICl molecules remained in the vibrationally excited states in our supersonic molecular beam. Based on the spectra near 304 nm, the quantum yield Ф of each channel, the curve crossing, and the branching fraction σ from each transition state were determined.

关 键 词：photofragment translational spectroscopy ICL PHOTODISSOCIATION hot band 

分 类 号：O643.1[理学—物理化学]