Tupikina Elena Yu, Denisov Gleb S, Tolstoy Peter M
Institute of Chemistry, St. Petersburg State University, Universitetsky pr. 26, 198504, Russia.
Department of Physics, St. Petersburg State University, Uljanovskaja 1, St. Petersburg, 198504, Russia.
J Comput Chem. 2019 Dec 15;40(32):2858-2867. doi: 10.1002/jcc.26066. Epub 2019 Sep 10.
The change of cooperativity of FH···Cl hydrogen bonds upon sequential addition of up to six FH molecules to the Cl first coordination sphere is investigated. The geometry of clusters [(FH) Cl] (n = 1…6) was calculated (CCSD/aug-cc-pVDZ) and compared with [(FH) F] clusters. The geometry is determined by the symmetry-driven electrostatic requirements and also by the fact that formation of each new FH···Cl bond creates a depression in the chlorine's electron cloud on the opposite side of Cl (σ-hole), which limits the range of directions available for subsequent H-bond formation. The mutual influence of FH···Cl hydrogen bonds is anticooperative-the addition of each FH molecule weakens H-bonds by 23-16% and decreases their covalent character (as seen by LMO-EDA decomposition and QTAIM analysis). Anticooperativity effects could be tracked by spectroscopic parameters (frequency of local HF mode ν , chemical shift δ , spin-spin coupling constants J , J , J and nuclear quadrupolar constants χ , χ , and χ . © 2019 Wiley Periodicals, Inc.
研究了在向氯的第一配位球中依次添加多达六个FH分子时，FH···Cl氢键协同性的变化。计算了[(FH)ₙCl]（n = 1…6）团簇的几何结构（CCSD/aug-cc-pVDZ），并与[(FH)ₙF]团簇进行了比较。几何结构由对称性驱动的静电需求决定，也由以下事实决定：每个新的FH···Cl键的形成会在Cl（σ-空穴）相对侧的氯电子云中产生凹陷，这限制了后续氢键形成可用的方向范围。FH···Cl氢键之间的相互影响是反协同的——每个FH分子的添加会使氢键减弱23 - 16%，并降低其共价性质（如通过LMO-EDA分解和QTAIM分析所见）。反协同效应可以通过光谱参数（局部HF模式的频率ν、化学位移δ、自旋-自旋耦合常数Jₕₕ、Jₕₗ、Jₗₗ和核四极常数χₕₕ、χₕₗ、χₗₗ）来追踪。© 2019威利期刊公司。
