在自行研制的具有恒温加热进样系统的激光质谱仪上获得了262～272 nm波段气相氯苯的(1+1)共振增强多光子电离/飞行时间质谱(REMPI-TOFMS)。研究表明,该波长范围内获得的光激发谱的光谱结构是氯苯第一激发态1B2(S1)振动能级的反映,对其中14条谱线进行了尝试性指认。分析了氯苯在266 nm波长处不同激光能量下的光电离质谱特点,讨论了造成77C6H+5质谱的非对称增宽的原因。实验研究了266 nm波长处氯苯分子离子信号强度与样品浓度之间的关系,估算出氯苯的探测限为ng/L量级。

The 1+1 two-photon resonant enhanced multiphoton ionization spectra of chlorobenzene were obtained at the range of 262～272 nm on the laser mass spectrometer with heatable sample inlet system which was designed by ourselves. The result shows that the structure of the excitation spectra in this wavelength range represents the first excited state 1B2(S1) of the chlorobenzene. 14 spectrum lines were assigned. The characteristics of the photon ionization mass spectrum at 266 nm were analyzed. The non-symmetric broadening of the mass spectrometry of the 77C6H+5 was analyzed. The relationship between the signal intensity of chlorobenzene and the sample concentration was studied. It is shown that the detection limit of the chlorobenzene is about ng/L range.