Volume 67 | Issue 5 | Year 2021 | Article Id. IJMTT-V67I5P512 | DOI : https://doi.org/10.14445/22315373/IJMTT-V67I5P512

In Chemical Graph Theory, several degree based topological indices were introduced and studied since 1972. Recently, Gutman considered a class of novel graph invariants of which the Sombor index was defined. In this paper, we introduce some new Sombor indices: the second, third, fourth and neighborhood (or fifth) Sombor indices of a graph. Furthermore, we compute the Sombor and neighborhood Sombor indices and their exponentials of some important nanostructures which appeared in nanoscience.

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V.R. Kulli, "Neighborhood Sombor Index of Some Nanostructues," *International Journal of Mathematics Trends and Technology (IJMTT)*, vol. 67, no. 5, pp. 101-108, 2021. *Crossref*, https://doi.org/10.14445/22315373/IJMTT-V67I5P512