物理化学学报 >> 1998, Vol. 14 >> Issue (11): 1007-1012.doi: 10.3866/PKU.WHXB19981109

研究论文 上一篇    下一篇

242-260nm波长区CS2分子的多光子解离电离

张立敏, 陈军, 戴静华, 王储记, 章弢, 陈从香, 马兴孝   

  1. 中国科学院选键化学开放实验室,中国科技大学化学物理系,合肥 230026
  • 收稿日期:1998-01-12 修回日期:1998-05-25 发布日期:1998-11-15
  • 通讯作者: 张立敏

The Multiphoton Dissociation and lonization of CS2 in the Range 242-260nm

Zhang Li-Min, Chen Jun, Dai Jing-Hua, Wang Chu-Ji, Zhang  Tao, Chen Cong-Xiang, Ma Xing-Xiao   

  1. Laboratory for Bond-selective Chemistry,Academy Sinica;Departmetn of Chemical Physics,University of Science and Technology of China,Hefei 230026
  • Received:1998-01-12 Revised:1998-05-25 Published:1998-11-15
  • Contact: Zhang Li-Min

摘要:

在242-260nm波长范围通过CS2分子的共振增强多光子电离(REMPI)获得了母体离子CS和碎片离子的分质量激发谱.在λ<246.4nm区间,CS激发谱上呈现出来源于CS2双光子电离的弥散谱带. 碎片离子激发谱的归属强烈提示多光子过程中有中性基电子态的CS和S(经由CS2的光解离)产生:(1)CS+的谱带主要来源于中性CS碎片经由A1Π←X1Σ+(v’’≤2)单光子跃迁产生的(1+1)共振增强电离,(2)除了部分S+的谱峰来自CS+的光解外,多数S+的锐谱峰来自中性S原子经由3p3(2D0)4p,3p3(4S0)np(n=6,7,8)←3p4 3pJ(J=2,1,0)双光子跃迁产生的(2+1)共振增强电离.

关键词: CS2分子, 光解离, CS碎片, S原子

Abstract:

 The mass-selected excitation spectra for parent ion CS and the fragmentation ions CS+, S+ and C+ are obtained by using the resonance-enhanced multiphoton ionization (REMPI)of CS2 in the range 242 260nm. It is shown that the diffuse bands of CS in range of λ<246.4nm are mainly from the two-photon ionization of CS2. It has been reasonably assumed from the assignments of excitation spectra for the fragments that the neutral CS and S are produced by the photodissociation of CS2 in the process, that is, (1) the bands of CS+ are mainly due to the (1+1) resonance-enhanced ionization via the one-photon transition of the fragment CS, (2) besides part of S+ spectral peaks are from the dissociation of CS+, most of S+ spectral peaks are due to the (2+1) resonance-enhanced ionization via the two-photon transition 3p3 (2D0) 4p, 3p3 (4S0) np (n=6,7,8)←3p4 3PJ (J=2,1,0) of S atoms.

Key words: CS2, Photodissociation, CS fragmentation, S atom