激光产生的钒硫簇离子的统计分布与结构探讨

以脉冲激光在高真空中溅射钒粉和硫粉的混合物，产生了一系列钒硫原子簇正负离子。根据对其实验记录的激光等离子体质谱进行分析，发现钒硫原子簇的化学键基本上是共价型的，对应于相同钒原子数目的正负离子的相对丰度分别符合于不同形式的对数正态分布。正离子的相对丰度随硫原子数的增加呈对数衰减，由此可以确定各种大小簇合物的簇骼与几何构型；负离子的相对丰度则基本上呈正常的正态分布，说明在簇骼上结合了不同数量硫原子的负离子之结构稳定性大致相近。在实验中还观察到一类硫原子含量较高的簇离子，其中的部分硫原子可能在本身成键形成环状的硫集团后，又与原来的簇骼结合，因而在硫原子数较多时它们的相对丰度符合另一条对数正态分布曲线。

Structural Studies of Laser Generated Vanadium-Sulphur Cluster Ions From Their Statistical Distributions

Vanadium-sulphur cluster ions of various sizes and compositions have been formed by laser ablating the mixture of sulphur and vanadium powders in high vacuum. By analyzing the mass spectra, it is found that the vanadium and sulphur atoms are bond by covalence bond in cluster,and the size-distribution of clusters with definite V atoms and different number of S atoms can be fitted by lognormal curves. For the cluster anions, the fitted curves are normal, but for the cluster cations, the fitted curves are monotonously decay, from which the cluster geometries can be determined. By further,it is found that another type of V-S cluster cations are formed sometimes, in which some sulphur atoms bond each other and form a monocyclic ring in clusters.