丙烯酰氯分子的气相光解动力学

Photodissociation of acryloyl chloride in the gas phase

利用时间分辨傅立叶变换红外(TR-FTIR)发射光谱研究了气相中CH2=CHCOCl分子的光解动力学.观测到振动激发的光解碎片分子CO(ν≤5),HCl(ν≤6),C2H2和相应的两个光解离通道:C-Cl键断裂和HCl消除通道.通过分析转动分辨的红外发射光谱得到CO和HCl的初始振转能量态分布,由此提出CH2=CHCOCl的气相光解机理并阐明了内转换等非绝热过程在影响反应途径中的关键作用.

The 193 nm photodissociation dynamics of CH 2 CHCOCl in the gas phase have been examined with the technique of time-resolved Fourier transform infrared emission （TR-FTIR） spectroscopy.Vibrationally excited photofragments of CO （v ≤ 5）,HCl （v ≤ 6）,and C 2 H 2 were observed and two photodissociation channels,the C-Cl fission channel and the HCl elimination channel have been identified.The vibrational and rotational state distributions of the photofragments CO and HCl have been acquired by analyzing their fully rotationally resolved v→v-1 rovibrational progressions in the emission spectra,from which it has been firmly established that the mechanism involves production of HCl via the four-center molecular elimination of CH 2 CHCOCl after its internal conversion from the S 1 state to the S 0 state.In addition to the dominant C-Cl bond fission along the excited S 1 state,the S 1 → S 0 internal conversion has also been found to play an important role in the gas phase photolysis of CH 2 CHCOCl as manifested by the considerable yield of HCl.