Results 21 to 30 of about 307,150 (283)
Aromaticity of aza aromatic molecules: prediction from Hückel theory with modified parameters [PDF]
Química Nova, 2023 Hückel theory is a simple and powerful method for predicting the molecular orbital and the energy of conjugated molecules. However, the presence of nitrogen atoms in aza aromatic molecules alters the Coulomb and resonance integrals owing to the ...
Inge M. Sutjahja +3 more
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The Total π-Electron Energy Saga
, 2017 The total π-electron energy, as calculated within the Hückel tight-binding molecular orbital approximation, is a quantum-theoretical characteristic of conjugated molecules that has been conceived as early as in the 1930s. In 1978, a minor modification of
I. Gutman, Boris Furtula
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Computing graph energy: An alternative approach [PDF]
Kragujevac Journal of Science, 2014 The characteristic polynomial corresponding to the adjacency matrix of a graph is obtained by the Faddeev-Leverrier algorithm. Subsequently, an improved numerical scheme, based on the Newton-Raphson algorithm and the Adomian decomposition method, is ...
Fatoorehchi Hooman +2 more
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Sum Rules and Ward Identities in the Kondo Lattice [PDF]
, 2005 We derive a generalized Luttinger-Ward expression for the Free energy of a many body system involving a constrained Hilbert space. In the large $N$ limit, we are able to explicity write the entropy as a functional of the Green's functions.
A. A. Abrikosov +8 more
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Electron Energy Studying of Molecular Structures via Forgotten Topological Index Computation
Journal of Chemistry, 2016 It is found from the earlier studies that the structure-dependency of total π-electron energy Eπ heavily relies on the sum of squares of the vertex degrees of the molecular graph. Hence, it provides a measure of the branching of the carbon-atom skeleton.
Wei Gao +3 more
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On the spectrum, energy and Laplacian energy of graphs with self-loops
Heliyon, 2023 The total energy of a conjugated molecule's π-electrons is a quantum-theoretical feature that has been known since the 1930s. It is determined using the Huckel tight-binding molecular orbital (HMO) method.
Ugasini Preetha P +2 more
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Comparing energy and Randic energy
Macedonian Journal of Chemistry and Chemical Engineering, 2013 The recently conceived Randić energy (RE) is examined, and its relation to the (earlier much studied) total π-electron energy (E) is investigated. Within classes of molecular graphs, there exists a relatively good (increasing) linear correlation between ...
Boris Furtula, Ivan Gutman
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On bounds for topological descriptors of φ-sum graphs
Journal of Taibah University for Science, 2020 The properties of chemical compounds are very important for the studies of the non-isomorphism phenomenon's related to the molecular graphs. Topological indices (TIs) are one of the mathematical tools which are used to study these properties.
Yu-Ming Chu +3 more
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Computing Connection-Based Topological Indices of Sudoku Graphs
Journal of Mathematics, 2022 A topological index (TI) is a function that associates a numeric number to the under-study molecular graph. The first TI based on distance was presented by Wiener to find the boiling point of paraffins.
Muhammad Basit Ali +2 more
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Absorption of Energy at a Metallic Surface due to a Normal Electric Field [PDF]
, 2000 The effect of an oscillating electric field normal to a metallic surface may be described by an effective potential. This induced potential is calculated using semiclassical variants of the random phase approximation (RPA).
Austin E J +7 more
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