Calculating Interaction Energies Using First Principle Theories: Consideration of Basis Set Superposition Error and Fragment Relaxation

Abstract

The use of computational chemistry tools has become prevalent in a wide variety of research areas. Many researchers are using computational chemistry as an additional tool to explore and gain insight into the problems they are researching. As such it is important to educate future scientists in the capabilities and proper implementation of theoretical tools. In this article we explain a difficult aspect of computational chemistry: calculating accurate interaction energy by correcting for basis set superposition error and fragment relaxation. There are four fundamental methods to calculate an interaction energy using ab initio theory, two of which take into account basis set superposition error. Using the methanol–water complex as a model, we demonstrate how to calculate an interaction energy using these four different methods. Additionally, we perform a comparison of the interaction energies and examine the magnitude of basis set superposition error as a function of basis set size. Fragment relaxation will be discussed in relation to these methods and is an indication of the magnitude of the inductive forces for each monomer.

The Effect of the Second Coordination Sphere on Electrochemistry of Niobium Fluoride Complexes in Alkali Halide Melts

“…23 This quantity characterizes the energy change of [NbF 7 ] complex in the system (without taking into account the complex interaction energy with the environment) compared to that of the free [NbF 7 ] complex. In terms of the BSSE theory (BSSE -basis set superposition error), 24,25 the E com energy is the energy of relaxation. electrode is presented in Fig.…”

Analysis of the basis set superposition error in molecular dynamics of hydrogen-bonded liquids: Application to methanol

“…The BSSE is especially prominent in systems with intermolecular hydrogen-bonds, [51][52][53][54][55][56][57] and is thus expected to influence the RDF of methanol. It has been shown that the calculation of the BSSE corrections can change their potential energy curves and surfaces, [58][59][60][61][62] and can alter the bond distances.…”

Catalyst design in C–H activation: a case study in the use of binding free energies to rationalise intramolecular directing group selectivity in iridium catalysis

“…Values E int and E dist were derived by employing the Boys-Bernardi counterpoise scheme, which calculates electronic energies of catalyst and substrate fragments from previously optimised geometries. 3,51,52 As detailed in Scheme 11, deconstructed directing group binding electronic energies for CF 2 H-containing substrate 4b were assessed. Consistent with the D(DG bind ) free energy calculations, moving from catalyst 2a to 2d progressively improves the overall binding electronic energy for the sulfonamide over the competing pyrazole (E bind ; blue).…”