Extremal topological indices of some nanostructures

Shivani Rai; Biswajit Deb; Zahid Raza; Sourav Mondal

doi:10.1016/j.heliyon.2023.e21223

Extremal topological indices of some nanostructures

Heliyon. 2023 Oct 21;9(11):e21223. doi: 10.1016/j.heliyon.2023.e21223. eCollection 2023 Nov.

Authors

Shivani Rai^{1

2}, Biswajit Deb¹, Zahid Raza³, Sourav Mondal^{4

5}

Affiliations

¹ Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136, India.
² The ICFAI University, Sikkim 737101, India.
³ Department of Mathematics, College of Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates.
⁴ Department of Mathematics, Sungkyunkwan University, Suwon 16419, Republic of Korea.
⁵ Department of Mathematics, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu-603 203, India.

Abstract

In this work, general formulas of degree-based and neighborhood degree sum-based topological indices for a 2D lattice of H-Naphtalenic nanotubes and pent-heptagonal nanosheets are determined. As an example, six neighborhood degree sum-based topological indices are computed using the obtained formula. Furthermore, the extremal cases of these nanostructures with a fixed number of blocks are characterized for a given degree-based or neighborhood degree sum-based topological index. Also a visual comparison of these indices is shown. Additionally, it is demonstrated how beneficial the indices are for representing structure-property relationships.

Keywords: H-Naphtalenic nanotubes; Neighborhood degree sum; Pent-heptagonal nanosheets; Topological index.