摘要
通过193nm光解丁烯酮分子产生乙烯基自由基(·C2H3).经射流冷却后,用另一束激光光解·C2H3,生成的氢原子碎片经共振增强多光子电离(REMPI)过程,记录氢离子信号随光解波长变化,得到20020～20070cm-1范围内乙烯基激发的转动分辨光谱.该谱对应于A$2A″(v′=0)%X$2A′(v″=0)跃迁的转动结构.结合量子化学理论计算、光谱拟合以及前人的研究结果,对该段光谱进行了完整的转动识别,确定了40条转动谱线的位置.由光谱拟合还得到A$2A″(v′=0)能级的预解离寿命为3.3ps,且不依赖于转动量子数.
The vinyl radical was generated by photolysing methyl vinyl ketone with 193 nm laser, then was excited and photodissociated by another laser in the 20020-20070 cm^-1 range. The dissociated H atom fragments were ionized and detected by （1＋1＇） resonance-enhanced multiphoton ionization（REMPI） process. The rotationally resolved action spectra of the A~^2A＂（v′=0）←X^A′（V″=0） band of the vinyl radical were recorded by monitoring the H^＋ ion intensity with dissociation laser wavelength. The corresponding assignments were obtained with the aid of ab initio calculations and spectroscopic simulations, and 40 rotational lines were definitely assigned. Additionally, the predissociative lifetime of the · C2H3 A~^2A＂（v′=0） state was 3.3 ps and independent of the rotational levels, which was derived from the linewidth.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2006年第1期6-10,共5页
Acta Physico-Chimica Sinica
关键词
乙烯基
共振增强多光子电离
转动光谱
预解离
Vinyl radical, Resonance-enhanced multiphoton ionization, Rotational spectroscopy,Predissociation
