Results 1 to 10 of about 229,792 (151)
Total π-electron energy and Laplacian energy: How far the analogy goes? [PDF]
Journal of the Serbian Chemical Society, 2007 The Laplacian energy LE is a newly introduced molecular-graph-based analog of the total π-electron energy E. It is shown that LE and E have a similar structure-dependency only when molecules of different sizes are compared, when a good linear correlation
Radenković Slavko, Gutman Ivan
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Bicyclic molecular graphs with the greatest energy [PDF]
Journal of the Serbian Chemical Society, 2008 The molecular graph Qn is obtained by attaching hexagons to the end vertices of the path graph Pn-12. Earlier empirical studies indicated that Qn has greatest energy among all bicyclic n-vertex (molecular) graphs.
IVAN GUTMAN +2 more
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Estimating the total π-electron energy [PDF]
Journal of the Serbian Chemical Society, 2013 The paper gives a short survey of the most important lower and upper bounds for total π-electron energy, i.e., graph energy (E). In addition, a new lower and a new upper bound for E are deduced, valid for general molecular graphs.
Gutman Ivan, Das Kinkar Ch.
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Iterative estimation of total π-electron energy [PDF]
Journal of the Serbian Chemical Society, 2005 In this work, the lower and upper bounds for total π-electron energy (E) was studied. A method is presented, by means of which, starting with a lower bound EL and an upper bound EU for E, a sequence of auxiliary quantities E0 E1, E2,… is computed, such ...
Türker Lemi, Gutman Ivan
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The Hückel total π-electron energy puzzle [PDF]
Journal of the Serbian Chemical Society, 2006 In spite of being based on drastic simplifications, the Hückel molecular orbital (HMO) quantum-mechanical model provides a reasonably good description of the properties of π-electrons in conjugated molecules.
Perić Miljenko +2 more
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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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Initial-state radiation measurement of the e^+e^- → π^+π^-π^+π^- cross section [PDF]
, 2012 We study the process e^+e^-→π^+π^-π^+π^-γ, with a photon emitted from the initial-state electron or positron, using 454.3 fb^(-1) of data collected with the BABAR detector at SLAC, corresponding to approximately 260 000 signal events.
Cheng, C. H. +8 more
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The McClelland approximation and the distribution of π-electron molecular orbital energy levels [PDF]
Journal of the Serbian Chemical Society, 2007 The total π-electron energy E of a conjugated hydrocarbon with n carbon atoms and m carbon–carbon bonds can be approximately calculated by means of the McClelland formula E = g SQRT(2mr), where g is an empirical fitting constant, g ≈ 0.9.
IVAN GUTMAN
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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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No Hückel graph is hyperenergetic [PDF]
Journal of the Serbian Chemical Society, 2000 If G is a molecular graph with n vertices and if λ1, λ2, ..., λn are its eigenvalues, then the energy of G is equal to E(G) = |λ1| + |λ2|+ ... + |λn|. If E(G) > 2n - 2, then G is said to be hyperenergetic.
Gutman I. +4 more
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