An Approach to Molecular Similarity using Density Functional Theory

Abstract

This paper describes an approach to molecular similarity using a Gaussian expansion for the density which simplifies the calculation of the Carbo-type molecular similarity index. In addition, we introduce the notion of a local similarity index. The local index uses the fragment density of a molecule to compute the index and allows parts of molecules to be compared to one another. Our approach to similarity is tested on a variety of small test cases; benzene and substituted benzenes, water, the water dimer, and complexes such as H 2 O-F - and H 2 O-Cl - . The results of these calculations are in qualitative agreement with previous calculations, and one's general intuition of chemical similarity