Abstract
For a given graph G, the Mostar index \(Mo(G)\) is the sum of absolute values of the differences between \(n_u(e)\) and \(n_v(e)\) over all edges \(e = uv\) of G, where \(n_u(e)\) and \(n_v(e)\) are, respectively, the number of vertices of G lying closer to vertex u than to vertex v and the number of vertices of G lying closer to vertex v than to vertex u. In this paper, the tree-type hexagonal systems (catacondensed hydrocarbons) with the least and the second least Mostar indices are determined. We also show some properties of tree-type hexagonal systems with the greatest Mostar index. And as a by-product, we determine the graph with the greatest Mostar index among tree-type hexagonal systems with exactly one full-hexagon. These results generalize some known results on extremal hexagonal chains.
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References
M. Arockiaraj, J. Clement, N. Tratnik, Mostar indices of carbon nanostructures and circumscribed donut benzenoid systems. Int. J. Quantum. Chem. 119, e26043 (2019)
A.T. Balaban, F. Harary, Chemical graphs—V: enumeration and proposed nomenclature of benzenoid cata-condensed polycyclic aromatic hydrocarbons. Tetrahedron 24(6), 2505–2516 (1968)
K. Balakrishnan, B. Brešar, M. Chagat, S. Klavžar, A. Vesel, P.Žigert Pleteršek, Equal opportunity networks, distance-balanced graphs, and Wiener game. Discrete Opt. 12, 150–154 (2014)
A.A. Dobrynin, E. Estaji, Wiener index of certain families of hexagonal chains. J. Appl. Math. Comput. 59, 245–256 (2019)
T. Došlić, I. Martinjak, R. Škrekovski, S.T. Spužević, I. Zubac, Mostar index. J. Math. Chem. 56, 2995–3013 (2018)
S. Gupta, M. Singh, Application of graph theory: relationship of eccentric connectivity index and Wiener’s index with anti-inflammatory activity. J. Math. Anal. Appl. 266, 259–268 (2002)
S. Gupta, M. Singh, A.K. Madan, Eccentric distance sum: a novel invariant for predicting biological and physical properties. J. Math. Anal. Appl. 275, 386–401 (2002)
I. Gutman, S.J. Cyvin, Introduction to the Theory of Benzenoid Hydrocarbons (Springer, Berlin, 1989)
F. Hayat, B. Zhou, On Mostar index of trees with parameters. Filomat 33, 6453–6458 (2019)
F. Hayat, B. Zhou, On cacti with large Mostar index. Filomat 33(15), 4865–4873 (2019)
S. Huang, S. Li, M. Zhang, On the extremal Mostar indices of hexagonal chains. MATCH Commun. Math. Comput. Chem. 84, 249–271 (2020)
A. Ilić, S. Klavžar, M. Milanović, On distance-balanced graphs. Eur. J. Combin. 31, 733–737 (2010)
J. Jerebic, S. Klavžar, D.F. Rall, Distance-balanced graphs. Ann. Combin. 12, 71–79 (2008)
S. Klavžar, I. Gutman, B. Mohar, Labeling of benzenoid systems which reflects the vertex-distance relations. J. Chem. Inf. Comput. Sci. 35, 590–593 (1995)
S. Klavžar, A bird’s eye view of the cut method and a survey of its applications in chemical graph theory. MATCH Commun. Math. Comput. Chem. 60, 255–274 (2008)
K. Kutnar, A. Malnič, D. Marušič, Š. Miklavič, Distance-balanced graphs: symmetry conditions. Discrete Math. 306, 1881–1894 (2006)
Molecular descriptors—the free online resource. http://www.moleculardescriptors.eu/dataset/dataset.htm. Accessed Dec 2017
A. Tepeh, Extremal bicyclic graphs with respect to Mostar index. Appl. Math. Comput. 355, 319–324 (2019)
L.Z. Zhang, F. Tian, Extremal catacondensed benzenoids. J. Math. Chem. 34, 111–122 (2003)
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The authors would like to express their sincere gratitude to all of the referees for their insightful comments and suggestions, which led to a number of improvements to this article.
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Kecai Deng is partially supported by NSFC (No.11701195) and by Scientific Research Funds of Huaqiao University (No.16BS808) and Shuchao Li is partially ssupported by NSFC (Nos. 11671164, 11271149).
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Deng, K., Li, S. Extremal catacondensed benzenoids with respect to the Mostar index. J Math Chem 58, 1437–1465 (2020). https://doi.org/10.1007/s10910-020-01135-0
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DOI: https://doi.org/10.1007/s10910-020-01135-0