Topological descriptors Subject

The structure of a chemical is responsible for the presence and magnitude of its properties. The properties can be energy levels and their derivatives, as well as physicochemical, or biological, properties. To avoid discrimination between the different properties (which are the subject of detailed consideration in Chapters 3, 4, and 6) in the context of quantitative relationships between structural descriptors (i.e., topological indices [TIs]) and various properties, we will use the broader abbreviation QSPR (Quantitative Structure-Property Relationship). 

The X-matrix, which consisted of QCT, constitutional, topological, geometrical and lipophilic descriptors was subjected to a GA within the Matlab toolbox.66 We refer... 

The second group of reactions involves the (4- -3) and (5 + 2) cycloadditions, in some cases being also pericyclic and therefore subject to the Woodward-Hoffmann rules, or transition metal catalyzed (Fig. 7). We use the (x+y) descriptor for the topological presentation of the number of atoms. 

Topological and topographical indices In QSP/AR, this class of descriptors is extensively used by chemists. Extensive literature on the subject exists, and many novel indices are still being introduced. Among the classic ones, the Wiener index is best known.This index is... 

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