Quantitative Determination of the Nature of Intermolecular Bonds by EDA Analysis

Abstract

In this chapter, the most common methods of analysis of the interaction energy between two moieties, as well as how this energy is distributed into components of different type and/or nature (electrostatic, exchange, polarization, charge transfer, etc.) are reviewed. Perturbation methods as well as strategies based on the use of standard supermolecular quantum chemical calculations are surveyed. Two different approaches are considered in the latter case: energy decompositions in the Hilbert (i.e. orbital) or in the real space. The focus is put on comparing allegedly equivalent terms, disclosing their similarities and differences. Advantages and disadvantages of the different schemes are also commented on. After a general discussion, we will focua on analyzing different energy components for different methods in a set of simple systems, going from fully covalent to weak intermolecular interactions.