Topological Properties of Benzenoid Systems. XXXVII. Characterization of Certain Chemical Graphs
نویسنده
چکیده
The importance of caterpillar trees in the topological theory of benzenoid systems lies in the following. Let B be a non-branched cata-condensed benzenoid hydrocarbon (that is a hydrocarbon containing linearly and angularly condensed rings). If we associate a symbol L to each linearly condensed ring (and also to the two terminal ones) and a symbol A to each angularly condensed ring, then the so-called L, ^ sequence [3,4] is obtained, which is of the form LAL'*A... Z > " M Z > . Let C(B) be the Clar graph [4, 5] corresponding to B. Let, in addi t ion, the sextet polynomial [6] of B be written in the form
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