Relations between Clar structures, Clar covers, and the sextet-rotation tree of a hexagonal system
نویسندگان
چکیده
منابع مشابه
A test of Clar aromatic sextet theory
The Clar aromatic sextet theory predicts that the intensity of cyclic conjugation in chevron-type benzenoid hydrocarbons monotonically decreases along the central chain. This regularity has been tested by means of several independent theoretical methods (by the energy effects of the respective sixmembered rings, as well as by their HOMA, NICS, and SCI values, calculated at the B3LYP/6-311G(d,p)...
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Pristine graphene is a semimetal and thus does not have a band gap. By making a nanometer scale periodic array of holes in the graphene sheet a band gap may form; the size of the gap is controllable by adjusting the parameters of the lattice. The hole diameter, hole geometry, lattice geometry, and the separation of the holes are parameters that all play an important role in determining the size...
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Kekule structures are transformed into the subspace of their double bonds to yield the correspondilng factor graphs, orig.inally called submolecules (8. E 1Bas i 1, Internat. J. Quantum Chem. 21 (1982) 771). A graiph-theoretical analysis of factor graphs is presented for certain classes o,f benzeno1i:d hydrocarbons. Such an analysis led to expressions for .the construction of sextet polynomials...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2008
ISSN: 0166-218X
DOI: 10.1016/j.dam.2007.08.047