复合物Mg^+-NCSCH_3,Ca^+-NCSCH_3光解离光谱研究  

Photodissociation Spectra of the Complexes Mg^+-NCSCH_3 and Ca^+-NCSCH_3

作　　者：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] 

机构地区：[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

出　　处：《化学学报》2005年第8期681-685,共5页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos. 20171014;20471018);广东省教育厅自然科学基金资助项目

摘　　要：研究了复合物Mg+-NCSCH3在230～440nm波段和Ca+-NCSCH3在320～560nm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.Photodissociation spectra of the complexes Mg+-NCSCH3 in the spectral region of 230 similar to 440 nm and Ca+-NCSCH3 in 320 similar to 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 (3(2)S -> 3(2)P for Mg+; 4(2)S -> 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.

关 键 词：激光光解 飞行时间质谱 金属离子-分子复合物 波段 光解离光谱 光诱导反应 

分 类 号：O621.13[理学—有机化学]