CH_3I的裂解与某些特殊的直线形三原子分子相似,有重要研究意义。Y.T.Lee等曾用266nm激光研究CH_3I分子束的光解,测量了CH_3碎片的高分辨飞行时间谱。我们利用自己设计制造的束源转动型分子束激光光解装置,用KrF激光(249nm)裂解CH_3I,载气为空气。用自制的四极质谱仪和离子计数检测系统,以及PAR的多通道讯号分析器,测量了Ⅰ碎片(M=127)的高分辨飞行时间谱,也得到Ⅰ~*和Ⅰ的两个峰。当分子束与 The cleavage of CH_3I is similar to that of some special linear three-atom molecules, which has important research significance. Y.T. Lee et al. Used 266nm laser to study the photodissociation of CH_3I molecular beam and measured the high-resolution time-of-flight spectra of CH_3 fragments. We use their own design and manufacture of beam source molecular beam laser photolysis device, with KrF laser (249nm) cracking CH_3I, the carrier gas is air. Using a home-made quadrupole mass spectrometer and ion counter detection system, and PAR’s multichannel signal analyzer, high-resolution time of flight spectra of fraction I (M = 127) were measured and two peaks of I ~ * and I were also obtained. When the molecular beam with