This paper is concerned with a generalization of the atom-bond sum-connectivity (ABS) index, devised recently in [A. Ali, B. Furtula, I. Redžepović, I. Gutman, Atom-bond sum-connectivity index, J. Math. Chem., 60 (2022), 2081-2093]. For a connected graph $ G $ with an order greater than $ 2 $, the general atom-bond sum-connectivity index is represented as $ ABS_\gamma(G) $ and is defined as the sum of the quantities $ (1-2(d_x+d_y)^{-1})^{\gamma} $ over all edges $ xy $ of the graph $ G $, where $ d_x $ and $ d_y $ represent the degrees of the vertices $ x $ and $ y $ of $ G $, respectively, and $ \gamma $ is any real number. For $ -10\le \gamma \le 10 $, the significance of $ ABS_\gamma $ is examined on the data set of octane isomers for predicting six selected physicochemical properties of the mentioned compounds; promising results are obtained when the approximated value of $ \gamma $ belongs to the set $ \{-3, 1, 3\} $. The effect of the addition of an edge between two non-adjacent vertices of a graph under $ ABS_\gamma $ is also investigated. Moreover, the graphs possessing the maximum value of $ ABS_{\gamma} $, with $ \gamma > 0 $, are characterized from the set of all connected graphs of a fixed order and a fixed (ⅰ) vertex connectivity not greater than a given number or (ⅱ) matching number.
Citation: Abeer M. Albalahi, Zhibin Du, Akbar Ali. On the general atom-bond sum-connectivity index[J]. AIMS Mathematics, 2023, 8(10): 23771-23785. doi: 10.3934/math.20231210
This paper is concerned with a generalization of the atom-bond sum-connectivity (ABS) index, devised recently in [A. Ali, B. Furtula, I. Redžepović, I. Gutman, Atom-bond sum-connectivity index, J. Math. Chem., 60 (2022), 2081-2093]. For a connected graph $ G $ with an order greater than $ 2 $, the general atom-bond sum-connectivity index is represented as $ ABS_\gamma(G) $ and is defined as the sum of the quantities $ (1-2(d_x+d_y)^{-1})^{\gamma} $ over all edges $ xy $ of the graph $ G $, where $ d_x $ and $ d_y $ represent the degrees of the vertices $ x $ and $ y $ of $ G $, respectively, and $ \gamma $ is any real number. For $ -10\le \gamma \le 10 $, the significance of $ ABS_\gamma $ is examined on the data set of octane isomers for predicting six selected physicochemical properties of the mentioned compounds; promising results are obtained when the approximated value of $ \gamma $ belongs to the set $ \{-3, 1, 3\} $. The effect of the addition of an edge between two non-adjacent vertices of a graph under $ ABS_\gamma $ is also investigated. Moreover, the graphs possessing the maximum value of $ ABS_{\gamma} $, with $ \gamma > 0 $, are characterized from the set of all connected graphs of a fixed order and a fixed (ⅰ) vertex connectivity not greater than a given number or (ⅱ) matching number.
[1] | A. M. Albalahi, E. Milovanović, A. Ali, General atom-bond sum-connectivity index of graphs, Mathematics, 11 (2023), 1–15. https://doi.org/10.3390/math11112494 doi: 10.3390/math11112494 |
[2] | A. Ali, B. Furtula, I. Redžepović, I. Gutman, Atom-bond sum-connectivity index, J. Math. Chem., 60 (2022), 2081–2093. https://doi.org/10.1007/s10910-022-01403-1 doi: 10.1007/s10910-022-01403-1 |
[3] | A. Ali, I. Gutman, I. Redžepović, Atom-bond sum-connectivity index of unicyclic graphs and some applications, Electron. J. Math., 5 (2023), 1–7. https://doi.org/10.47443/ejm.2022.039 doi: 10.47443/ejm.2022.039 |
[4] | T. A. Alraqad, I. Ž. Milovanović, H. Saber, A. Ali, J. P. Mazorodze, Minimum atom-bond sum-connectivity index of trees with a fixed order and/or number of pendent vertices, 2022, arXiv: 2211.05218. |
[5] | J. A. Bondy, U. S. R. Murty, Graph theory, Springer, 2008. |
[6] | E. Estrada, L. Torres, L. Rodríguez, I. Gutman, An atom-bond connectivity index: Modelling the enthalpy of formation of alkanes, Indian J. Chem. Sect. A, 37 (1998), 849–855. |
[7] | E. Estrada, Atom-bond connectivity and the energetic of branched alkanes, Chem. Phys. Lett., 463 (2008), 422–425. https://doi.org/10.1016/j.cplett.2008.08.074 doi: 10.1016/j.cplett.2008.08.074 |
[8] | S. Fajtlowicz, On conjectures of Graffiti-Ⅱ, Congr. Numer., 60 (1987), 187–197. |
[9] | J. L. Gross, J. Yellen, Graph theory and its applications, 2 Eds., New York: Chapman & Hall/CRC, 2005. https://doi.org/10.1201/9781420057140 |
[10] | I. Gutman, Degree-based topological indices, Croat. Chem. Acta, 86 (2013), 351–361. http://dx.doi.org/10.5562/cca2294 doi: 10.5562/cca2294 |
[11] | I. Gutman, B. Furtula, Recent results in the theory of Randić index, Kragujevac: University of Kragujevac, 2008. |
[12] | X. L. Li, I. Gutman, Mathematical aspects of Randić-type molecular structure descriptors, Kragujevac: University of Kragujevac, 2006. |
[13] | X. L. Li, Y. T. Shi, A survey on the Randić index, MATCH Commun. Math. Comput. Chem., 59 (2008), 127–156. |
[14] | L. Lovász, M. D. Plummer, Matching theory, North Holland, 1986. |
[15] | Molecular descriptors. Available from: https://web.archive.org/web/20180912171255if_/http://www.moleculardescriptors.eu/index.htm |
[16] | V. Maitreyi, S. Elumalai, S. Balachandran, The minimum ABS index of trees with given number of pendent vertices, 2022, arXiv: 2211.05177. |
[17] | S. Noureen, A. Ali, Maximum atom-bond sum-connectivity index of $n$-order trees with fixed number of leaves, Discrete Math. Lett., 12 (2023), 26–28. https://doi.org/10.47443/dml.2023.016 doi: 10.47443/dml.2023.016 |
[18] | M. Randić, The connectivity index 25 years after, J. Mol. Graph. Model., 20 (2001), 19–35. https://doi.org/10.1016/S1093-3263(01)00098-5 doi: 10.1016/S1093-3263(01)00098-5 |
[19] | M. Randić, On characterization of molecular branching, J. Am. Chem. Soc., 97 (1975), 6609–6615. https://doi.org/10.1021/ja00856a001 doi: 10.1021/ja00856a001 |
[20] | A. Shabbir, M. F. Nadeem, Computational analysis of topological index-based entropies of carbon nanotube Y-junctions, J. Stat. Phys., 188 (2022), 31. https://doi.org/10.1007/s10955-022-02955-x doi: 10.1007/s10955-022-02955-x |
[21] | X. D. Song, J. P. Li, J. B. Zhang, W. H. He, Trees with the second-minimal ABC energy, AIMS Math., 7 (2022), 18323–18333. https://doi.org/10.3934/math.20221009 doi: 10.3934/math.20221009 |
[22] | Y. F. Tang, D. B. West, B. Zhou, Extremal problems for degree-based topological indices, Discrete Appl. Math., 203 (2016), 134–143. https://doi.org/10.1016/j.dam.2015.09.011 doi: 10.1016/j.dam.2015.09.011 |
[23] | S. Wagner, H. Wang, Introduction to chemical graph theory, Boca Raton: CRC Press, 2018. |
[24] | B. Zhou, N. Trinajstić, On a novel connectivity index, J. Math. Chem., 46 (2009), 1252–1270. https://doi.org/10.1007/s10910-008-9515-z doi: 10.1007/s10910-008-9515-z |