Results 141 to 150 of about 3,864 (163)

Resonance in catacondensed benzenoid hydrocarbons

International Journal of Quantum Chemistry, 1997
We consider resonance in cata-condensed benzenoids having six and seven fused benzene rings. The resonance relationship between the Kekule valence structures of the molecules is represented by the resonance graphs in which the vertices represent the Kekule valence structures, and the edges, the presence of the quantum chemical resonance integral ...
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A Periodic Table for Benzenoid Hydrocarbons

1990
The formulas for all benzenoid hydrocarbons are found in Table PAH6 which has x,y-coordinates of (d s , NIc). Recursive construction of this table was accomplished using an aufbau principle. This table complies to a sextet rule analogous to the octet rule for the periodic table of elements, and d s is analogous to the outer-shell electronic ...
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Mathematics of Periodic Tables for Benzenoid Hydrocarbons

Journal of Chemical Information and Modeling, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
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Clar's valence structures of benzenoid hydrocarbons

Journal of the Chemical Society, Faraday Transactions 2, 1988
The properties of Clar's valence structures for unbranched catacondensed benzenoid systems have been considered. These molecules can be represented as caterpillar trees, i.e. ayclic graphs with side branches of length one only. The sextet polynomials of the benzenoids are simply related to the characteristic polynomials of corresponding caterpillar ...
Sherif El-Basil, Milan Randi?
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Polarography of Benzenoid Aromatic Hydrocarbons

Russian Chemical Reviews, 1969
This review summarises the results of the study of the reduction and oxidation in protogenic, aprotic, and strongly acidic solutions of benzenoid polynuclear aromatic hydrocarbons whose molecules do not contain electrochemically active substituents.
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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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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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Local aromatic properties of benzenoid hydrocarbons

Pure and Applied Chemistry, 1980
Abstract
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On dioxo derivatives of benzenoid hydrocarbons

Journal of Molecular Structure: THEOCHEM, 1999
Abstract Extending a problem occurring in connection with the stability order of the tautomers of hypericin, we examine the topological factors influencing the stability of the isomeric dioxo derivatives of benzenoid hydrocarbons, in particular the rules determining the number of Kekule structures in them. Depending on the position of the oxo groups,
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Semiempirical Valence Bond Views for Benzenoid Hydrocarbons

1990
Because the π-networks of benzenoid hydrocarbons are the classical prototypical example of delocalized bonding, they provide a crucial test for chemical-bonding theories. Here there is revealed a systematic organization for valence-bond views to describe such π-bonding.
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