Results 171 to 180 of about 5,564 (213)

Clar Theory for Molecular Benzenoids

The Journal of Physical Chemistry A, 2009
Eric Clar's ideas concerning "aromatic sextets" are extended to a quantitative format in terms of a polynomial called the "Clar 2-nomial", along with related derivative quantities. The quantification is successfully tested to make correlations with a selection of numerical data, including resonance energies, bond lengths, and NICS ring-aromaticity ...
Anirban, Misra, D J, Klein, T, Morikawa
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Algebraic Kekulé Structures of Benzenoid Hydrocarbons

Journal of Chemical Information and Computer Sciences, 2004
An algebraic Kekulé structure of a benzenoid hydrocarbon is obtained from an ordinary Kekulé structure by inscribing into each hexagon the number of pi-electrons which (according to this Kekulé structure) belong to this hexagon. We show that in the case of catafusenes, there is a one-to-one correspondence between ordinary and algebraic Kekulé ...
Gutman, Ivan, Vukičević, Damir, Graovac, Ante, Randić, Milan   +3 more
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Nonaromatic benzenoid hydrocarbons

Pure and Applied Chemistry, 1990
Abstract
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“Tschitschibabin type biradicals”: benzenoid or quinoid?

Physical Chemistry Chemical Physics, 2015
Revisiting the history: towards the better understanding of open shell singlet biradicaloids.
Ravat, P., Baumgarten, M.
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Embedding in Benzenoid Hydrocarbons

Journal of Chemical Information and Computer Sciences, 1996
Using the embedding scheme and a rule we proposed previously, in this work we discuss common eigenvalues and their degeneracies in benzenoid molecular graphs.
Jun Liu, Yuansheng Jiang
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Bond resonance energies of polycyclic benzenoid and non-benzenoid hydrocarbons

Journal of the Chemical Society, Perkin Transactions 2, 1996
The bond resonance energy represents the contribution of a given π bond in a molecule to the topological resonance energy. Bond resonance energies for 43 typical polycyclic conjugated hydrocarbons and five of their molecular ions have been evaluated and critically examined.
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Polycyclische benzenoide Systeme

Monatshefte f�r Chemie Chemical Monthly, 1988
Superposition of significant electron structures is used to estimate the mesomerism stabilization of polycyclic benzenoid systems by consideration of the number ofKekule structures and of benzenoid interactions between them. General formulae and stability rules are given for many classes of cata and pericondensed molecules.
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Benzenoid rings resonance energies and local aromaticity of benzenoid hydrocarbons

Journal of Computational Chemistry, 2018
In this article, we consider partitioning of the analytical expression for resonance energy (RE) in smaller benzenoid hydrocarbons, to individual benzenoid rings of polycyclic molecules. The analytical expression for molecular RE, available since 1976, is given by the count of all linearly independent conjugated circuit in all Kekulé structures in a ...
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Almost-isospectral benzenoid systems

Chemical Physics Letters, 1991
Abstract The concept of almost-isospectral molecular graphs is defined and its importance for the experimental testing of Huckel molecular-orbital theory is pointed out. Examples of almost isospectral benzenoid systems are reported.
Ivan Gutman, Svetlana Marković
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Perimeter Topology of Benzenoid Polycyclic Hydrocarbons.

ChemInform, 2005
The equivalence of the perimeter topological equations derived by Dias and the 13 possible modes of hexagon adjacency in fused benzenoid systems subsequently presented by Cyvin, Gutman, and collaborators is shown. The aufbau principle for generation of all fused total resonant sextet (TRS) benzenoid hydrocarbons is proved.
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