The formation of hydrogenated carbon clusters by laser ablation

✍ Scribed by Nan Zhang; Zhongde Yu; Xiaojun Wu; Zhen Gao; Qihe Zhu; Fanao Kong

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 491 KB
• Volume: 205
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)89225-7

✦ Synopsis

Hydrogenated carbon cluster ions (C,Hz ) were produced by laser ablation of aromatic compounds and studied by a timeofflight mass spectrometer. A series of clusters with about 8 hydrogen atoms for the middle-mass region (30 x n-z 60) and a new set of clusters with specific number of hydrogen atoms for the high-mass region (n> 60) were observed. Some structural features are 1. Introduction The study of carbon clusters has been a fascinating research field since Kroto et al. [ 1 ] proposed the structure of Cao and other fullerenes, produced by laser vaporization in a flow of inert gas. It is also of interest to deal with hydrogenated carbon clusters, which may be the same kind of species as the soot formed in the combustion flame of hydrocarbons. The study on hydrogenated carbon clusters also helps us to understand the structure of pure carbon fullerenes. Only a few papers have been reported on experimental observations of these clusters. Heath et al.

[ 2 ] first reported the results for low-mass hydrogenated carbon clusters C,,H& (n < 30). The clusters were generated from laser vaporization of graphite in a hydrogen seeded carrier gas flow. In the case of 100 Torr of partial pressure for Hz, C,,H6+ was found for even n numbers. A long carbon chain model was suggested to explain this observation. In a similar experiment, Rohlling [3] found that in middle-mass region (n = 30-60), hydrogenated clusters with up to eleven hydrogen atoms, with m=2 and 3 as preference numbers, were formed for both odd and even n. In the above cases, the hydrogen concentration in the carrier gas was so low that only a few hydrogen