F Koorepazan-Moftakhar - Department of Pure Mathematics, University of Kashan, Kashan, I.R.Iran
A.R Ashrafi - Department of Nanocomputing, Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan, I.R.Iran

Graovac and Pisanski [1] introduced a modification of the Wiener index by symmetry group of the moleculargraph under consideration. They combined the topology and symmetry of a molecule to obtain some theoretical resultswith the best correlation by some physico–chemical properties of molecules under consideration. The aim of this paperis to continue this work by presenting new modification of the eccentric connectivity index and computing them fornanocones.

Nanocones; symmetry; eccentric connectivity index