Wiener Index of Hexagonal Systems
نویسندگان
چکیده
The Wiener index W is the sum of distances between all pairs of vertices of a (connected) graph. Hexagonal systems (HS’s) are a special type of plane graphs in which all faces are bounded by hexagons. These provide a graph representation of benzenoid hydrocarbons and thus find applications in chemistry. The paper outlines the results known for W of the HS: method for computation of W , expressions relating W with the structure of the respective HS, results on HS’s extremal w.r.t. W , and on integers that cannot be the W -values of HS’s. A few open problems are mentioned. The chemical applications of the results presented are explained in detail. Mathematics Subject Classifications (2000): 05-02, 05C12, 92-02, 92E10, 68R10.
منابع مشابه
Second and Third Extremals of Catacondensed Hexagonal Systems with Respect to the PI Index
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