X-ray Raman spectra of the carbon K-edge have been recorded using 6.461 keV radiation for a petroleum asphaltene. By comparison with coronene, graphite, and paraffin standards, the asphaltene spectrum is seen to be composed of contributions from saturated and aromatic carbon species. The information contained in the carbon K-edge was extracted with bulk (approximately 1 mm) sensitivity, because...

The structure and stability of ca. 100 nonplanar constitutional isomers of the coronene molecule of general formula C(24)H(12) have been estimated by semiempirical and by ab initio calculations. The isomers studied are unbranched cyclic catacondensed structures and fall into two classes, viz., the belt (B) and the Moebius (M) type. The calculations have shown some of the M-isomers to be more st...

An efficient algorithm leading to the Fries canonical structure is presented for benzenoid hydrocarbons. This is a purely topological approach, which is based on adjacency matrices and the Hadamard procedure of matrix multiplication. The idea is presented for naphthalene, as an example. The Fries canonical-structures are also derived for anthracene, coronene, triphenylene, phenanthrene, benz[a]...

Dicoronylene Isomers, UV/VIS Absorption Spectra, Fluorescence Spectra The non-alternant hydrocarbon cyclopenta[l,2-a:3,4,5-b'c']dicoronene (3) has been pre­ pared by aluminium chloride catalyzed dimerization o f coronene (1). The UV/VIS absorption spectrum, fluorescence spectrum and fluorescence quantum yield o f 3 is reported and com ­ pared with that o f the alternant isomer benzo[l,2,3-bc:4,...