摘要
在自制的交叉分子-离子束串级飞行时间质谱仪上，以激光溅射的方式，产生了一系列含有一个硫原子和一个氢原子与含有两个硫原子的杂碳原子簇正负离子、经“质量门”选出单一质量的簇离子，与氮气的超声分子束交叉碰撞，然后分析其碰撞碎片．研究结果确定了这些簇离子的结构，两个杂原子分别位于碳链的两端．对碎片离子的分析还揭示了这些簇离子的主要解离通道及其与成簇碳原子数和所带电荷极性的关系，发现当成簇碳原子数较少时，簇离子中最薄弱的是S－C键，随着残链的增长，与硫原子相邻的C－C键变得更为薄弱；实验中存在着多次碰撞的机会，因而各碎片离子还有可能进一步解离．
On a home-made crossed ion-molecular beam tandem time-of flight mass spectrometer,carbon cluster ions with two hetercratoms, CnSH± and CnSt were produced from laser ablation,mass-selected, and collided with pulsed nitrogen beam. From mass analysis of the fragment ions,structures of the cluster ions were characterized as linear, with two hetero-atoms locating on both ends of the carbon chain. The experimental results also revealed the main dissociation channel of the cluster ions. According to the results, for most cluster ions studied in the experiment, the weakest bond is the C-C bond next to the sulfur atom, but in some smaller cluster ions, S-C bond is easier to break. Under the experimental condition, cluster ions may suffer multiple collisions, so fragment ions produced from stepwise dissociation process were observed.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1997年第4期328-334,共7页
Acta Physico-Chimica Sinica
基金
国家杰出青年科学基金
国家教委"跨世纪人才计划’基金
关键词
碰撞诱导解离
解离通道
杂碳原子簇
C_nSH~±, C_nSt_2~± Collision-induced dissociation, Dissociation channel
