激光作用于稠环芳烃及其衍生物产生碳原子簇的负离子质谱研究

在自制的装置上以脉冲激光束作用于多种稠环芳烃及衍生物,产生各种大小的碳原子簇与它们的化合物,对这些簇负离子的质谱分析表明,其中质量较高的离子具有球烯(Fullerene)的空间封闭体构型,信号强度最突出的是C~-_(50),次为C~-n,而C~-(60)在实验记录的多数质谱中并不突出;质量较低的离子的构型则是直链状的,其组成为C~-_n和C_nX~-(X因样品的不同分别为N、B、H、P和OH),而C_nX~-因其杂原子X的组成的不同,n或者必须为偶数、或者必须为奇数;质量靠近样品分子量的离子则仍为环状构型,其中保留了较多数量的氢原子。

Mass Spectrometry of Carbon Cluster Anions Generated with Laser Ablation of Polycyclic Aromatic Compounds

Carbon clusters of variety of sizes and their compounds have been generated by laser ablation of different kinds of polycyclic aromatic hydrocarbons and their derivatives. According to the analysis of their mass spectra data of the cluster anions, the anions of higher mass are all fullerens. Among these fullerene anions, C50- has special high ion intensity and CM is next. The intensity of anion of buckminsterfullerene is not special in most recorded spectra. The anions of low mass are linear with compositions of C.- or C.X-(X = N,B,H,P,OH depending on diffferent samples). Among these C.X-, the number of carbon atom ?has either be odd or be even depending on the composition of heteroatom X. The anions with mass near the molecular weight of the sample still keep the planar cyclic configuration and original amount of hygrogen atoms.