Szeged index of armchair polyhex nanotubes

Topological indices of nanotubes are numerical descriptors that are derived from graph of chemical compounds. Such indices based on the distances in graph are widely used for establishing relationships between the structure of nanotubes and their physico-chemical properties. The Szeged index is obtained as a bond additive quantity where bond contributions are given as the product of the number of atoms closer to each of the two end points of each bond. In this paper we find an exact expression for Szeged index of TUVC6[2p, q], the armchair polyhex nanotubes, using a theorem of A. Dobrynin and I. Gutman on connected bipartite graphs (see Ref [1]).