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Algebraic Kekulé Structures of Benzenoid Hydrocarbons
Journal of Chemical Information and Computer Sciences, 2004An 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 ...
Ivan Gutman +3 more
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On Some Exponential Structure Descriptors and Their Applications to Benzenoid Hydrocarbons
International Journal of Quantum ChemistryIn this article, we compute exponential topological indices of benzenoid hydrocarbons using MATLAB based on their edge connectivity and investigate their correlation with several thermodynamic properties, including boiling point, entropy, enthalpy of ...
Prosanta Sarkar +2 more
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The Non-Benzenoid Aromatic Hydrocarbon Pentalene
Nature, 1948IT is an interesting fact that neitherjpentalene (1), nor heptalene (2), nor any derivatives of them have been definitely reported as being synthesized1 or found to occur naturally. Azulene (3) is, on the other hand, a substance which can be made by the established procedures of organic chemistry and it is known in Nature.
D P, CRAIG, A, MACCOLL
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Mathematical methods in the applied sciences, 2020
In this paper, we provide efficient regression models for correlating the π‐electronic energies of carbon nanotubes and nanocones. First, a computational technique for determining distance‐based, eccentricity‐based, degree‐distance‐based, and degree ...
Sakander Hayat +3 more
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In this paper, we provide efficient regression models for correlating the π‐electronic energies of carbon nanotubes and nanocones. First, a computational technique for determining distance‐based, eccentricity‐based, degree‐distance‐based, and degree ...
Sakander Hayat +3 more
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Algebraic Kekulé Formulas for Benzenoid Hydrocarbons
Journal of Chemical Information and Computer Sciences, 2004By 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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Perimeter Topology of Benzenoid Polycyclic Hydrocarbons.
ChemInform, 2005The 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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Quality testing of distance-based molecular descriptors for benzenoid hydrocarbons
, 2020In this paper, we investigate the prediction power of all the well-known distance-based molecular structure descriptors in the literature for 22 lower polycyclic aromatic hydrocarbons (PAHs).
Sakander Hayat +3 more
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Results on the Estrada Indices of Benzenoid Hydrocarbons
Polycyclic aromatic compounds (Print), 2020The spectral moments of the edge adjacency matrix and adjacency matrix recently have been successfully employed in quantitative structure–property relationship and quantitative structure–activity relationship studies of alkanes, alkyl halides, benzyl ...
A. Jahanbani +2 more
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The evaluation of moments for benzenoid hydrocarbons
Theoretica Chimica Acta, 1995A systematic derivation of moments for polyhexes is presented, covering the tenth and twelfth members for the first time. The total Huckel π-electron energy is computed in terms of moments with desired precision. Equations governing various molecular fragments are useful for enumerating embeddings of acyclic chains (rooted trees) in polyhexes.
Yuansheng Jiang +2 more
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