Results 171 to 180 of about 12,581 (214)

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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Domination in Benzenoids

2010
VCU Theses and ...
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Algebraic Kekulé Formulas for Benzenoid Hydrocarbons

Journal of Chemical Information and Computer Sciences, 2004
By assigning two pi-electrons of CC double bonds in a Kekulé valence structure to a benzene ring if not shared by adjacent rings and one pi-electron if CC double bond is shared by two rings we arrived at numerical valence formulas for benzenoid hydrocarbons.
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Benzenoids with Repeated Units

1988
Benzenoids with repeated (identical) units have been encountered in several places of the preceding chapters. Already the single linear and zigzag chains (see, e.g. Fig. 4.9 or CHART 6-II) may be considered as (trivial) benzenoids with repeated units.
S. J. Cyvin, I. Gutman
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Benzenoid Systems: Basic Concepts

1988
The main topic of the present book is the enumeration of Kekule structures in benzenoid hydrocarbons. Since enumeration is essentially a mathematical procedure, it is beneficial to seek for an appropriate mathematical representation of benzenoid hydrocarbons as well as of Kekule structures.
S. J. Cyvin, I. Gutman
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