化学学报 ›› 2005, Vol. 63 ›› Issue (8): 681-685. 上一篇    下一篇

研究论文

复合物Mg-NCSCH3, Ca-NCSCH3光解离光谱研究

胡义华*1,林清华1,张兴初1,陈丽1,王小涓2,刘海川3,杨世和*3   

  1. (1广东工业大学应用物理学院 广州 510090)
    (2广东工业大学继续教育学院 广州 510090)
    (3香港科技大学化学系 香港 九龙)
  • 投稿日期:2004-09-14 修回日期:2004-12-14 发布日期:2010-12-10
  • 通讯作者: 胡义华

Photodissociation Spectra of the Complexes Mg-NCSCH3 and Ca-NCSCH3

HU Yi-Hua*1, LIN Qing-Hua1, ZHANG Xing-Chu1, CHEN Li1, WANG Xiao-Juan2, LIU Hai-Chuan3, YANG Shi-He*3   

  1. (1 School of Applied Physics, Guangdong University of Technology, Guangzhou 510090)
    (2 School of Continual Education, Guangdong University of Technology, Guangzhou 510090)
    (3 Department of Chemistry, Hong Kong University of Science and Technology, Kowloon, Hong Kong)
  • Received:2004-09-14 Revised:2004-12-14 Published:2010-12-10
  • Contact: HU Yi-Hua

研究了复合物Mg-NCSCH3在230~440 nm波段和Ca-NCSCH3在320~560 nm波段的光解离光谱. 复合物Mg-NCSCH3, Ca-NCSCH3光诱导反应的产物质谱表明有非反应猝灭产物Mg(Ca), C—S键断裂产物Mg(Ca)NC 和Mg(Ca)NCS以及重排反应产物Mg(Ca)-CHSH通道. 在原子跃迁谱线(32S→32P, 对于Mg; 42S?42P, 对于Ca)的红和蓝两边, Mg-NCSCH3的光解离光谱由两个宽峰组成; 而对于Ca-NCSCH3, 则是由三个谱峰构成. CIS/6-311++G**等级上, 对应于基态构型的Mg-NCSCH3电子态跃迁能量和振子强度与实验光谱较为一致; 而Ca-NCSCH3有较大的差别. 这是因为CIS方法忽略电子相关效应, 而Ca-based的跃迁中3d和4s轨道间存在较强的混合所致.

关键词: 金属离子-分子复合物, 激光光解, 飞行时间质谱

Photodissociation spectra of the complexes Mg-NCSCH3 in the spectral region of 230~440 nm and Ca-NCSCH3 in 320~560 nm were studied. Mass spectra of the products of photo-induced reaction of the complexes Mg-NCSCH3 and Ca-NCSCH3 exhibits the presence of Mg(Ca) from nonreaction quenching, Mg(Ca)NC and Mg(Ca)NCS from the rupture of S-C bonds, and rearrangement products Mg(Ca)-CHSH. The photodissociation spectra consist of two broad peaks for Mg-NCSCH3, and three broad peaks for Ca-NCSCH3 on the red and blue sides of atomic transition (32S→32P for Mg; 42S→42P for Ca). The calculated absorption spectrum corresponding to the minimum-energy structure agrees well with the experimental spectrum for Mg-NCSCH3, but poorly for Ca-NCSCH3. The reasons are that CIS method neglected correlation effects and orbital mixing occured between 3d and 4s during Ca-based transition.

Key words: metal cation-molecule complex, laser photodissociation, time-flight mass spectrum