The Wiener Polynomial Derivatives and Other Topological Indices in Chemical Research

A single number, representing a chemical structure, in graph-theoretical terms, is called a topological descriptor. It must be a structural invariant, i.e., it does not depend on the labeling or the pictorial representation of a graph. If such a descriptor correlates with a molecular property, it can be denominated as a topological index (TI). Despite the considerable loss of information by the »projection« of a structure to a single number, topological indices have found broad applications in the correlation (estimation and prediction) of several molecular properties. Another representation that has gained particular attention, both from the theoretical point of view and applications, is by polynomials.