作　　者： ; ; ; ; ; ; ;

机构地区： 广东工业大学应用数学学院

出　　处： 《化学学报》 2005年第8期681-685,共5页

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

领　　域： [理学] [理学] [理学] [理学]