Interacting Quantum Atoms Approach and Electrostatic Solvation Energy: Assessing Atomic and Group Solvation Contributions

Abstract

The interacting quantum atoms (IQA) method decomposes the total energy of a molecular system in terms of one‐ and two‐center (atomic) contributions within the context of the quantum theory of atoms in molecules. Here we incorporate electrostatic continuum solvent effects into the IQA energy decomposition. To this end, the interaction between the solute electrostatic potential and the solvent screening charges as defined within the COSMO solvation model is now included in a new version of the PROMOLDEN code, allowing thus to apply IQA in combination with COSMO‐quantum chemical methods as well as to partition the electrostatic solvation energy into effective atomic and group contributions. To test the robustness of this approach, we carry out COSMO‐HF/aug‐cc‐pVTZ calculations followed by IQA calculations on more than 400 neutral and ionic solutes extracted from the MNSol database. The computational results reveal a detailed atomic mapping of the electrostatic solvation energy that is useful to assess to what extent the solvation energy can be decomposed into atomic and group contributions of various parts of a solute molecule, as generally assumed by empirical methodologies that estimate solvation energy and/or logP values.

Photochemistry in Real Space: Batho‐ and Hypsochromism in the Water Dimer

“…For this endeavour, one would have to consider how either the solvent or peptidic surroundings modify the one‐ and two‐particle density matrices of the examined excited states. Some progress in this direction has been made, as in the case of solvent effects in a continuum approximation for GSs [86] …”

“…Some progress in this direction has been made, as in the case of solvente ffects in ac ontinuum approximation for GSs. [86]…”

QM/MM Energy Decomposition Using the Interacting Quantum Atoms Approach

“… 21 Furthermore, it has been shown that the IQA net atomic energies can easily absorb the electrostatic continuum-solvent effects, allowing thus the partition of solvation energies into effective atomic and group contributions. 22 …”

Proton leap: shuttling of protons onto benzonitrile

“…For this purpose, the Interacting Quantum Atoms methodology 21,22 (IQA) was employed, which has so far been successfully utilized for analysis of diverse systems, properties and processes. 23–41 It enables quantification of classical and non-classical interaction terms among selected fragments (the fragments being BN & PCH + , BN & H + , PC & H + , or BN & H + & PC), but also energetical properties of the fragments themselves when their geometry and the environment modify upon reaction advancement. The paper is organized as follows: Section 2 contains details of the computational procedure; the results and their discussion are presented in Section 3; the conclusions are summarized in Section 4.…”