Mohammad Reza Farahani, Connective Eccentric Index of Circumcoronene Homologous Series of Benzenoid Hk, ILCPA Volume 32, International Letters of Chemistry, Physics and Astronomy (Volume 32) https://www.scipress.com/ILCPA.32.71 Abstract: Let G be a molecular graph, a topological index is a numeric quantity related to G which is invariant under graph automorphisms. The eccentric connectivity index ξ(G) is defined as ξ(G) = ∑<sub>vV(G)</sub> d x ε(v) where dv, ε(v) denote the degree of vertex v in G and the largest distance between vand any other vertex u of G. The connective eccentric index of graph G is defined as C<sup>ξ</sup>(G) = ∑<sub>vV(G)</sub> d<sub>v</sub> /ε(v) In the present paper we compute the connective eccentric index of CircumcoroneneHomologous Series of Benzenoid H<sub>k</sub> (k ≥ 1). Keywords: Benzenoid, Connective Eccentric Index, Eccentric Connectivity Index, Molecular Graph