总的来看,sigma-hole作用有以下的规律: 对于卤素,sigma-hole的大小按F<Cl<Br<I的顺序增加,在溶液相阴离子识别中只有Br I是有效的 对于ChB、PnB和TrB供体原子(也就是C、N、O三族)来说,每族中周期较大的元素都具有更大的金属性质和高共价性的趋势。因此, Sb Bi Sn Pb可能不能产生更大的sigma-hole,因为...
在sigma-hole作用的规律中，氮唑阳离子扮演了核心角色，它表现出三种主要的次级作用：芳环氢键、阴离子-π+电荷作用以及卤键，这些作用力抗衡了阴离子的聚合趋势（图A）。卤键，包括经典的卤键、索烃生成、超分子识别和click反应，是分子间相互作用力之一，强度受溶剂和电荷密度影响。在不同溶剂中，如丙酮...
Sigma (σ)-holes are electron-deficient regions that arise from the anisotropic distribution of electron density on the atom of group 14 (tetrels), 15 (pnictogens), 16 (chalcogens), and 17 (halogens) elements when covalently bonded to electron-withdrawing groups. Named after the donor atom'...
用Multiwfn+VMD可以极其容易地绘制，看 使用Multiwfn+VMD快速地绘制静电势着色的分子范德华表面图和分子间...
However, cocrystallization through sigma hole (蟽-hole)-based modern interactions is a breakthrough in crystal engineering. This 蟽-hole mediated non-covalent interaction uniquely contributes to supramolecular chemistry through different subgroups viz halogen bonding (XB), chalcogen bonding (ChB), ...
The term "sigma-hole" originally referred to the electron-deficient outer lobe of a half-filled p (or nearly p) orbital involved in forming a covalent bond. If the electron deficiency is sufficient, there can result a region of positive electrostatic potential which can interact attractively (no...
For the first time, sigma (σ)- and lone-pair (lp)-hole site-based interactions of SF4 and SeF4 molecules in seesaw geometry with NH3 and FH Lewis bases were herein comparatively investigated. The obtained findings from the electrostatic potential analysis outlined the emergence of sundry holes...
sigma-Hole and LP-Hole Interactions of Pnicogen center dot center dot center dot Pnicogen Homodimers under the External Electric Field Effect: A Quantum Me... sigma-Hole and lone-pair (lp)-hole interactions within sigma-hole center dot center dot center dot sigma-hole, sigma-hole center dot...
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