ABSTRACT
Graphs and their generalizations are successfully used to model structural objects, relations, and process dynamics in chemical, physical, biological, social, and information systems. Methods of graph theory are necessary tools for the analysis of structure of complex networks arising in these fields [7,8]. One of the approaches in studying graph structure is quantifying structural information by various quantitative measures. Usually, a quantitative graph measure is a graph invariant that maps a set of graphs to a set of numbers such that invariant values coincide for isomorphic graphs. In this chapter, we deal with quantitative methods for analyzing structures of molecular graphs that are the standard representation of structure of chemical compounds in organic chemistry. Many invariants belong to the molecular structure descriptors, called topological indices, that are nowadays extensively used in theoretical chemistry for the characterization of molecular complexity and for the design of
quantitative structure-property relations and quantitative structure-activity relations including pharmacologic and biological activities [2-5,14,28,44-46,49].
