STRUCTURES OF CARBON CLUSTERS FROM POLYCHLORINATED GRAPHITIC PRECURSORS - INVESTIGATIONS OF C12CLX-10) USING THE ION CHROMATOGRAPHY METHOD((X=0)

Various C12Clx+ ions (x = 0-10) are formed from electron impact on dec achloroacenaphthene, C12Cl10. The structures of these ions are determi ned using ion chromatography. It is found that the graphitic carbon ba ckbone persists down to C12Cl4+. Small amounts of monocyclic structure s appear for C12Cl6+ and C12Cl4+ and are exclusive for C-12(+). The li near structure first appears at C12Cl4+ and is exclusive for C12Cl2+ a nd C12Cl+. For the most part, these results are consistent with predic tions from semiempirical PM3 calculations, indicating thermochemistry plays a major role in determining isomer distributions. In several cas es, other factors have to be considered, the most important being isom erization barriers and the effect of entropy. Doubly charged ions are observed for a significant number of cases. Graphitic structures disap pear below C12Cl62+ and are replaced by monocyclic and linear isomers, again consistent with PM3 calculations.