ABSTRACT
S.C. Basak, B.D. Gute and G.D. Grunwald Natural Resources Research Institute, University of Minnesota-Duluth,
Duluth, MN 55811, USA
A current trend in quantitative structure-property/activity relationship (QSPR/ QSAR) studies is the use of theoretical molecular descriptors that can be calculated directly from molecular structure. One advantage of such descriptors is that they can be calculated for any chemical structure, real or hypothetical. Topological indices (TIs) or numerical graph invariants constitute an important subset of these theoretical descriptors. TIs are derived from different classes of weighted graphs, representing various levels of chemical structural information. They are numerical quantifiers of molecular topology and encode information regarding the size, shape, branching pattern, cyclicity, and symmetry of molecular graphs. The Wiener index, different types of connectivity indices, and complexity or information theoretic topological indices have been widely used in QSAR/QSPR research.
