Growth functions, structural properties and energy transfer in model hydrocarbon compounds

Abstract

The effect of unsubstituted polycyclic aromatic hydrocarbons composed of 3, 4, and 5 benzenold rings on the growth effect of E. coli has been investigated. A criterion for growth enhancement is an angular acene molecular geometry. However, the linear acenes, tetracene and pentacene, as well as the angular chrysene and 1, 2, 3, 4-dibenzanthracene, inhibit growth. A review of crystal structure studies of spiro carbon hydrocarbons and spiro-ketohydrocarbons is given and a description of a novel way of solving the crystallographic phase problem, visual packing analysis, is described. The method was used to solve the crystal structure of spiro (5.5) undeca-1, 4, 7, 10-tetraene-3, 9- dione, and structural parameters of this compound are detailed. The results of ground state molecular orbital calculations of a family of dienone compounds and a family of bridged biphenyl compounds are reported. The transfer of energy in the second excited state of bis (2,2'- biphenylene) methane, or spirobifluorene, is investigated using fluorescence depolarization as a probe. Fluorescence depolarization does occur in S2, but it was not possible to determine if the mechanism is one of interchromophoric transfer or vibronic dipole coupling.