Results 21 to 30 of about 3,914 (183)
Stability order of isomeric benzenoid hydrocarbons and Kekulé structure count [PDF]
Journal of the Serbian Chemical Society, 2009 The commonly accepted opinion that the thermodynamic stability of isomeric benzenoid hydrocarbons (assessed by their total π-electron energy and various resonance energies) increases with increasing number of Kekulé structures is shown to be violated in ...
SLAVKO RADENKOVIĆ, IVAN GUTMAN
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Wiener Index of Edge Thorny Graphs of Catacondensed Benzenoids
Mathematics, 2020 The Wiener index is a topological index of a molecular graph, defined as the sum of distances between all pairs of its vertices. Benzenoid graphs include molecular graphs of polycyclic aromatic hydrocarbons.
Andrey A. Dobrynin, Ali Iranmanesh
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New bounds and approximations for total π-electron energy: A critical test [PDF]
Kragujevac Journal of Science, 2014 The quality and correlating ability of some recently deduced bounds and approximate formulas for total π-electron energy are tested on a sample of 106 Kekuléan benzenoid hydrocarbons.
Gutman Ivan +2 more
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Aromaticity-Induced Spin State Switching and High-Spin States in Non-Alternant Polyradicals. [PDF]
J Comput ChemThe peculiar topology of some non‐alternant systems allows such a degree of freedom in favored spin‐alignment between unpaired electrons that the polyradical can be in low‐, intermediate‐, and high‐spin ground state. Thus, the modulation of resonance energy upon distortions of pro‐aromatic units via external stimuli may result in switching the lowest ...
Betkhoshvili S +3 more
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A test of Clar aromatic sextet theory [PDF]
Journal of the Serbian Chemical Society, 2013 The Clar aromatic sextet theory predicts that the intensity of cyclic conjugation in chevron-type benzenoid hydrocarbons monotonically decreases along the central chain. This regularity has been tested by means of several independent theoretical
Gutman Ivan +3 more
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On some extended energy of graphs and their applications [PDF]
Yugoslav Journal of Operations ResearchIn this paper, we established a relation between the extended energy of graphs such as the first and second Zagreb energy, Randić energy, reciprocal Randić energy, and the atom-bond connectivity energy with some thermodynamic properties of benzenoid ...
Sarkar Prosanta +3 more
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On a class of approximate formulas for total ח-electron energy of benzenoid hydrocarbons [PDF]
Journal of the Serbian Chemical Society, 2001 The method for obtaining approximate formulas of the (n, m)-type for the total -electron energy of benzenoid hydrocarbons (communicated in J. Serb. Chem. Soc. 54 (1989) 189) is simplified and extended so as to include arbitrary spectral moments.
Gutman Ivan, Soldatović Tanja
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The Wiener polarity index of benzenoid systems and nanotubes [PDF]
, 2017 In this paper, we consider a molecular descriptor called the Wiener polarity index, which is defined as the number of unordered pairs of vertices at distance three in a graph.
Tratnik, Niko
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Degrees of projections of rank loci [PDF]
, 2014 We provide formulas for the degrees of the projections of the locus of square matrices with given rank from linear spaces spanned by a choice of matrix entries.
Aluffi, Paolo
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Number of Benzenoid Hydrocarbons [PDF]
Zeitschrift für Naturforschung A, 1986 The number of benzenoid hydrocarbons with h hexagons can be estimated by means of the formula Bh = 0.045-3/2 (5 .4 )h . The analogous estimate for the number of catacondensed benzenoids is Ch = 0.049 h-5/4 (4.27)h.
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