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Master Connectivity Index and Master Connectivity Polynomial
Current Computer Aided-Drug Design, 2010We give the standard expressions of the Zagreb indices, Randić indices and their variants. Then we present the master connectivity index and show how this index can generate all connectivity indices of both varieties. We also present the master connectivity polynomial and show the relationship between this polynomial and the master connectivity index ...
Vukičević, Damir +4 more
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External Factor Variable Connectivity Index
Journal of Chemical Information and Computer Sciences, 2003A new variable index, external factor variable connectivity index (EFVCI), is proposed, in which the atomic attribute is divided into two parts. The innate part is denoted as outer-shell electrons and external part or perturbation by other atoms is represented as summation, multiplied by a variable x, of squared reciprocal matrix of i row (corresponds ...
Hu, Qian Nan +7 more
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The Vertex-Connectivity Index Revisited
Journal of Chemical Information and Computer Sciences, 1998We report a search for optimum molecular descriptors based on the connectivity index. A suggestion made by several authors that the exponent -0.5 used in the standard formula for computing the connectivity index may not be the optimum for modeling some molecular properties was reexamined.
Trinajstić, Nenad +4 more
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Molecular Connectivity and Retention Indexes
Journal of Pharmaceutical Sciences, 1977The molecular connectivity indexes, chi, of some alcohols, ethers, esters, and ketones did not correlate very well with their retention volumes in some GLC systems. It was concluded that the utility of chi for the prediction of biological activities could prove rather limited.
Y, Michotte, D L, Massart
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The sum-connectivity index--an additive variant of the Randic connectivity index.
Current computer-aided drug design, 2013This review discusses structure-property modeling applications of a novel variant of the Randic connectivity index that is called the sum-connectivity index. We compare published one-descriptor quantitative structure-property relationship (QSPR) models obtained with the new sum-connectivity index and with the Randic connectivity index, called here the ...
Lučić, Bono +8 more
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Bounds for the Randić Connectivity Index
Journal of Chemical Information and Computer Sciences, 1999For a saturated hydrocarbon with n carbon atoms and m carbon-carbon bonds and with Randic connectivity index chi, two functions, L = L(n,m) and U = U(n,m), are determined, such that L < or = chi < U. These bounds are better than those previously reported; for most chemically relevant values of n and m there exist hydrocarbons for which chi = L or chi =
, Gutman, , Araujo, , Morales
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Variable Connectivity Index for Cycle-Containing Structures
Journal of Chemical Information and Computer Sciences, 2001In the early applications of the connectivity index the index was empirically modified for some properties of cyclic structures by subtracting 1/2 from the computed value based solely on valence of vertices in the molecular graph. In this article we looked into the origin of this heuristic adjustment of the connectivity indices for cyclic structures ...
Vikić-Topić, Dražen +2 more
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2010
In this report, we present a novel variant of the connectivity index that we call the sum-connectivity index. This is the additive version of the connectivity index introduced in 1975 by Milan Randić. Initially the Randić index has been introduced as a structural descriptor called branching index that later became well-known Randić connectivity index ...
Nikolić, Sonja +2 more
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In this report, we present a novel variant of the connectivity index that we call the sum-connectivity index. This is the additive version of the connectivity index introduced in 1975 by Milan Randić. Initially the Randić index has been introduced as a structural descriptor called branching index that later became well-known Randić connectivity index ...
Nikolić, Sonja +2 more
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On the maximum connective eccentricity index among k-connected graphs
Discrete Mathematics, Algorithms and Applications, 2020The connective eccentricity index (CEI for short) of a graph [Formula: see text] is defined as [Formula: see text], where [Formula: see text] is the degree of [Formula: see text] and [Formula: see text] is the eccentricity of [Formula: see text] in [Formula: see text].
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Chemical Physics Letters, 2009
The Randić (product-)connectivity index and its derivative called the sum-connectivity index are compared and it is shown that these both descriptors correlate well among themselves and with the Pi-electronic energies of benzenoid hydrocarbons.
Lučić, Bono +2 more
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The Randić (product-)connectivity index and its derivative called the sum-connectivity index are compared and it is shown that these both descriptors correlate well among themselves and with the Pi-electronic energies of benzenoid hydrocarbons.
Lučić, Bono +2 more
openaire +2 more sources