On the edge eccentric and modified edge eccentric connectivity indices of linear benzenoid chains and double hexagonal chains

Abstract

Let G be a molecular graph. The edge eccentric connectivity index of G, ξec(G), is defined as ξec(G)=∑f∈E(G)deg(f).ecc(f), where deg(f) denotes the degree of edge f and ecc(f) is the largest distance between f and any other edge g of G. The modified edge eccentric connectivity index of G, Λec(G), is defined as Λec(G)=∑f∈E(G)S(f).ecc(f), where S(f) denotes the sum of the degrees of edges neighborhoods of edge f. In this paper, exact formulas for the edge eccentric connectivity index and modified edge eccentric connectivity index of linear benzenoid chains and double hexagonal chains were computed.