University of KashanIranian Journal of Mathematical Chemistry2228-64895Supplement 120141201The First Geometric–Arithmetic Index of Some Nanostar Dendrimers16554110.22052/ijmc.2014.5541ENA.MadanshekafSemnan UniversityM.MoradiSemnan UniversityJournal Article20130325Dendrimers are highly branched organic macromolecules with successive layers or generations of branch units surrounding a central core [1,4]. These are key molecules in nanotechnology and can be put to good use. In this article, we compute the first geometricarithmetic index of two infinite classes of dendrimers.University of KashanIranian Journal of Mathematical Chemistry2228-64895Supplement 120141201The Laplacian Polynomial and Kirchhoff Index of the k-th Semi Total Point Graphs715685810.22052/ijmc.2014.6858ENZ.MehranianDepartment of Mathematics, University of Qom, Qom, IranJournal Article20140604The k-th semi total point graph of a graph G, , is a graph obtained from G by adding k vertices corresponding to each edge and connecting them to the endpoints of edge considered. In this paper, a formula for Laplacian polynomial of in terms of characteristic and Laplacian polynomials of G is computed, where is a connected regular graph.The Kirchhoff index of is also computed.University of KashanIranian Journal of Mathematical Chemistry2228-64895Supplement 120141201Flow Polynomial of some Dendrimers1720759110.22052/ijmc.2014.7591ENH.SharifiIslamic Azad UniversityG. H.Fath-TabarUniversity of KashanJournal Article20130612Suppose G is an nvertex and medge simple graph with edge set E(G). An integervalued function f: E(G) → Z is called a ﬂow. Tutte was introduced the ﬂow polynomial F(G, λ) as a polynomial in an indeterminate λ with integer coefficients by F(G,λ) In this paper the Flow polynomial of some dendrimers are computed.University of KashanIranian Journal of Mathematical Chemistry2228-64895Supplement 120141201The Neighbourhood Polynomial of some Nanostructures2125761810.22052/ijmc.2014.7618ENS.AlikhaniYazd University0000-0002-1801-203XE.MahmoudiYazd UniversityJournal Article20140906The neighbourhood polynomial G , is generating function for the number of faces of each cardinality in the neighbourhood complex of a graph. In other word $N(G,x)=sum_{Uin N(G)} x^{|U|}$, where N(G) is neighbourhood complex of a graph, whose vertices are the vertices of the graph and faces are subsets of vertices that have a common neighbour. In this paper we compute this polynomial for some nanostructures.University of KashanIranian Journal of Mathematical Chemistry2228-64895Supplement 120141201Perfect Matchings in Edge-Transitive Graphs2733777210.22052/ijmc.2014.7772ENA.MarandiUniversity of TehranA. H.NejahUniversity of TehranA.BehmaramUniversity of TabrizJournal Article20131204We find recursive formulae for the number of perfect matchings in a graph G by splitting G into subgraphs H and Q. We use these formulas to count perfect matching of P hypercube Qn. We also apply our formulas to prove that the number of perfect matching in an edge-transitive graph is , where denotes the number of perfect matchings in G, is the graph constructed from by deleting edges with an end vertex in {u,v}.University of KashanIranian Journal of Mathematical Chemistry2228-64895Supplement 120141201The Center and Periphery of Composite Graphs3544777310.22052/ijmc.2014.7773ENZ.YarahmadiIslamic Azad UniversityS.MoradiArak UnversityJournal Article20140104The center (periphery) of a graph is the set of vertices with minimum (maximum) eccentricity. In this paper, the structure of centers and peripheries of some classes of composite graphs are determined. The relations between eccentricity, radius and diameter of such composite graphs are also investigated. As an application we determine the center and periphery of some chemical graphs such as nanotorus and nanotubes covered by C4.University of KashanIranian Journal of Mathematical Chemistry2228-64895Supplement 120141201Relation Between Wiener, Szeged and Detour Indices4551777610.22052/ijmc.2014.7776ENN.AzimiSrtt Univ.M.RoumenaSrtt Univ.M.GhorbaniDepartment of mathematics, Shahid Rajaee Teacher Training UniversityJournal Article20140214In theoretical chemistry, molecular structure descriptors are used to compute properties of chemical compounds. Among them Wiener, Szeged and detour indices play significant roles in anticipating chemical phenomena. In the present paper, we study these topological indices with respect to their difference number.