Laboratorium für Organische Chemie, ETH Zurich , Vladimir-Prelog-Weg 2, CH-8093 Zurich, Switzerland.
J Am Chem Soc. 2017 Sep 20;139(37):13126-13140. doi: 10.1021/jacs.7b06997. Epub 2017 Sep 5.
London dispersion constitutes one of the fundamental interaction forces between atoms and between molecules. While modern computational methods have been developed to describe the strength of dispersive interactions in the gas phase properly, the importance of inter- and intramolecular dispersion in solution remains yet to be fully understood because experimental data are still sparse in that regard. We herein report a detailed experimental and computational study of the contribution of London dispersion to the bond dissociation of proton-bound dimers, both in the gas phase and in dichloromethane solution, showing that attenuation of inter- and intramolecular dispersive interaction by solvent is large (about 70% in dichloromethane), but not complete, and that current state-of-the-art implicit solvent models employed in quantum-mechanical computational studies treat London dispersion poorly, at least for this model system.
伦敦分散力是原子间和分子间的基本相互作用力之一。虽然已经开发出现代计算方法来正确描述气相中分散相互作用的强度，但在溶液中，分子间和分子内分散力的重要性仍有待充分理解，因为在这方面实验数据仍然很少。本文报道了一项详细的实验和计算研究，研究了伦敦分散力对质子结合二聚体键离解的贡献，包括在气相和二氯甲烷溶液中，结果表明，溶剂对分子间和分子内分散相互作用的衰减很大（在二氯甲烷中约为 70%），但并非完全衰减，并且当前量子力学计算研究中使用的最先进的隐式溶剂模型对伦敦分散力的处理效果很差，至少对于这个模型系统是如此。
