WEAKLY BOUND CARBON-CARBON BONDS IN ACENAPHTHYLENE DERIVATIVES

摘要

In this study, a class of acenaphthylene derivatives is shown to contain weak central carbon-carbon bonds that may be easily cleaved under combustion or even at ambient conditions to yield persistent free diradicals. Hexaphenylethane was also chosen as a molecule of interest due to its great resonance stabilization and long-standing history within the chemistry community. The C-C bond dissociation energy of hexaphenylethane was calculated to be 13.5 kcal/mol, without considering zero point vibrational energy. All calculations were performed with the recently developed M06-2X density functional and the 6-31+G(d,p) basis set. The types of molecules presented here are proposed as strong possibilities for the natural existence of free radicals in young and mature soot. The computational study is supplemented by experimental characterization of soot particles freshly produced from premixed ethylene flames using micro-FTIR, with an emphasis on identifying surface radical content.