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Symmetry 2010, 2(3), 1390-1400; doi:10.3390/sym2031390

How to Find the Fries Structures for Benzenoid Hydrocarbons

1,2,* , 2
1 Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawińskiego 5a, 02-106 Warsaw, Poland 2 Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
* Author to whom correspondence should be addressed.
Received: 3 February 2010 / Revised: 4 June 2010 / Accepted: 28 June 2010 / Published: 6 July 2010
(This article belongs to the Special Issue Aromaticity and Molecular Symmetry)
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An efficient algorithm leading to the Fries canonical structure is presented for benzenoid hydrocarbons. This is a purely topological approach, which is based on adjacency matrices and the Hadamard procedure of matrix multiplication. The idea is presented for naphthalene, as an example. The Fries canonical-structures are also derived for anthracene, coronene, triphenylene, phenanthrene, benz[a]pyrene, and one large benzenoid system. The Fries concept can be convenient for obtaining Clar structures with the maximum number of sextets, which in turn effectively represent π-electron (de)localization in benzenoid hydrocarbons.
Keywords: aromaticity; benzenoid hydrocarbons; graph topology; fries structure aromaticity; benzenoid hydrocarbons; graph topology; fries structure
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Ciesielski, A.; Krygowski, T.M.; Cyrański, M.K. How to Find the Fries Structures for Benzenoid Hydrocarbons. Symmetry 2010, 2, 1390-1400.

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