Electrotopological matrix

The (/, y)th elements of this matrix are given by the contribution of the path /, j (of length k) to the higher order connectivity index The electrotopological matrix for 3-methylhexane is illustrated in Table 7. 

Table 7 Illustration of Several Novel Matrices for Graph G Electrotopological matrix...

H -state index = hydrogen electrotopological state index electrotopological state indices > heteroatom-corrected extended adjacency matrix —> extended adjacency matrices... 

It can be noted that function i was used by Ivanciuc to define the —> distance-valency matrices, function was used by Kier-Hall to define the —> electrotopological state indices, function y was proposed by Randic to calculate the —> alimented valence of vertices, and function y was proposed by Estrada in the generalized molecular-graph matrix, where x is a user-defined parameter or a parameter to be optimized during the searching for the best QSAR correlations. 

It can be noted that the definition of this local vertex invariant is very similar to that of the electrotopological state index Si, but this is based on absolute values of the perturbation terms Ij — Ii, with the consequence that the sum of A/j over all the vertices is different from zero. Absolute values were introduced to avoid the sum of the matrix off-diagonal elements results in zero for any weighting scheme w considered. 

For molar volume (Vm) with index based on distance matrix and electrotopological states SdOfacid and SsOH(acid) (r > 0.99). 

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