ON THE $M$-POLYNOMIAL AND SOME TOPOLOGICAL INDICES OF THE PARA-LINE GRAPHS OF THE NANOSTRUCTURE $TUC_4C_8(R)$

The study of topological indices associated with molecular graphs is very helpful in understanding many of their physico-chemical properties. Various degree based topological indices such as generalized Randi$\acute{c}$ index, Zagreb index, Arithmetic-Geometric index and harmonic index are found to be particularly useful in the study of many molecular nanostructures. In this paper, we obtain the $M$-polynomial of the para-line graphs of the $2D$-lattice, nanotube and nanotorus of $TUC_4C_8(R)\left[p,q\right]$, by means of which, we compute some of their topological indices.