Development and application of evaluation method for molecular similarity based on quantum chemical theory

Abstract

An issue in development of functional molecules is to search a molecule which shows expected properties. A concept of molecular similarity is one of the strategies for searching molecules of interest. Because of its importance, various similarities have been suggested so far. In this study, we propose a method for quantitative evaluating molecular similarity on the basis of electronic structure calculations. Herein we suggest 9 types of descriptors for molecular similarity. They are calculated using electronic-structure calculations in information of electronic ground state, electronic excited state, and the vibrational modes of the electronic ground state are provided. We have applied our method to classify a set of organic molecules including 5 carotenoids and 11 hydrocarbons. It has been successful to distinguish carotenoids and other molecules without referring to their chemical formula.