Řezáč Jan, de la Lande Aurélien
Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 166 10, Prague, Czech Republic.
Institut de Chimie Physique, CNRS, Université Paris Saclay, 91405, Orsay, France.
Chemphyschem. 2023 Sep 15;24(18):e202300329. doi: 10.1002/cphc.202300329. Epub 2023 Jul 24.
Charge transfer is one of the mechanisms involved in non-covalent interactions. In molecular dimers, its contribution to pairwise interaction energies has been studied extensively using a variety of interaction energy decomposition schemes. In polar interactions such as hydrogen bonds, it can contribute ten or several tens of percent of the interaction energy. Less is known about its importance in higher-order interactions in many-body systems, mainly because of the lack of methods applicable to this problem. In this work, we extend our method for the quantification of the charge-transfer energy based on constrained DFT to many-body cases and apply it to model trimers extracted from molecular crystals. Our calculations show that charge transfer can account for a large fraction of the total three-body interaction energy. This also has implications for DFT calculations of many-body interactions in general as it is known that many DFT functionals struggle to describe charge-transfer effects correctly.
电荷转移是非共价相互作用所涉及的机制之一。在分子二聚体中，利用各种相互作用能分解方案对其对成对相互作用能的贡献进行了广泛研究。在诸如氢键等极性相互作用中，它可占相互作用能的10%或几十%。关于其在多体系统高阶相互作用中的重要性，人们了解较少，主要是因为缺乏适用于此问题的方法。在这项工作中，我们将基于约束密度泛函理论（DFT）的电荷转移能量量化方法扩展到多体情况，并将其应用于从分子晶体中提取的三聚体模型。我们的计算表明，电荷转移可占三体相互作用总能量的很大一部分。这对于多体相互作用的一般DFT计算也有影响，因为众所周知，许多DFT泛函难以正确描述电荷转移效应。
