On a Graph - Theoretical Approach to Kekule Structures * . Novel Identities of Sextet Polynomials and a Relation to Clar ' s Sextet Theory
نویسندگان
چکیده
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 of some types of benzenoid hydroc·arbons containing as many as ten rings in a few seconds without drawing any graphs!.
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