On the Sanskruti Index of Circumcoronene Series of Benzenoid

Fourth Zagreb index of Circumcoronene series of Benzenoid

A topological index of a graph is a numeric quantity related to a structure of a molecule which is invariant under graph automorphism. Recently, Ghorbani and Hosseinzadeh introduced Fourth Zagreb index of graphs. In this paper we determine a closed formula of this new topological index of the famous Benzenoid family named Circumcoronene series of Benzenoid Hk.

Calculating the hyper–Wiener index of benzenoid hydrocarbons

A method for the calculation of the hyper–Wiener index (WW ) of a benzenoid system B is described, based on its elementary cuts. A pair of elementary cuts partitions the vertices of B into four fragments, possessing nrs , r, s = 1, 2 vertices. WW is equal to the sum of terms of the form n11 n22 + n12 n21 . The applicability of the method is illustrated by deducing a general expression for WW of...

On the Irregularity of Some Molecular Structures

Measures of the irregularity of chemical graphs could be helpful for QSAR/QSPR studies and for the descriptive purposes of biological and chemical properties, such as melting and boiling points, toxicity and resistance. Here we consider the following four established irregularity measures: the irregularity index by Albertson, the total irregularity, the variance of vertex degrees and the Collat...

On discriminativity of vertex-degree-based indices

A recently published paper [T. Došlić, this journal 3 (2012) 25-34] considers the Zagreb indices of benzenoid systems, and points out their low discriminativity. We show that analogous results hold for a variety of vertex-degree-based molecular structure descriptors that are being studied in contemporary mathematical chemistry. We also show that these results are straightforwardly obtained by u...

On General Sum-Connectivity Index of Benzenoid Systems and Phenylenes