Algorithms to calculate the distance numbers and the Wiener indices of linear and cylindrical poly (p-phenylene) in terms of number of hexagonal rings

The compounds of poly (p-phenylene) are important materials for electro-optical and electronic applications. Algorithms for the calculation of the distances and hence the Wiener indices (W) of linear poly (p-phenylene) and cylindrical poly (p-phenylene) systems have been developed that require only the number of hexagonal rings present in the systems. Ambient conditions density and the bulk modulus of linear poly (p-phenylenes) with two to six phenyl rings have correlated with W ^1/4. Cylindrical poly (p-phenylene) systems with 5 and 6 phenyl rings are found to occur as intervening strands in between two caps of fullerene cages.