Original scientific paper

https://doi.org/10.5562/cca2000

Forcing, Freedom, & Uniqueness in Graph Theory & Chemistry

Douglas J. Klein orcid.org/0000-0002-5354-0065 ; Texas A&M University at Galveston, Galveston, TX 77553
Vladimir Rosenfeld ; Texas A&M University at Galveston, Galveston, TX 77553

Abstract

Harary’s & Randić’s ideas of “forcing” & “freedom” involve subsets of double bonds of Kekule structure such as to be unique to that Kekule structure. Such forcing sets are argued to be greatly generalizable to deal with various other coverings, and thence forcing seems to be fundamental, and of notable potential utility. Various forcing invariants associated to (molecular) graphs ensue, with illustrative (chemical) ex-amples and some mathematical consequences being provided. A complementary “uniqueness” idea is not-ed, and the general characteristic of “derivativity” of “forcing” is established (as is relevant for QSPR fit-tings). Different ways in which different sorts of forcings arise in chemistry are briefly indicated.(doi: 10.5562/cca2000)

Keywords

forcing; freedom; Kekule structures; Clar structures; Pauling bond orders; conjugated circuits; resonance structures; maximum matchings; maximal matchings; radicals

Hrčak ID:

122279

URI

https://hrcak.srce.hr/122279

Publication date:

30.4.2014.

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