Zhuo Hongying, Li Qingzhong, Li Wenzuo, Cheng Jianbo
The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, People's Republic of China.
J Chem Phys. 2014 Dec 28;141(24):244305. doi: 10.1063/1.4904294.
Ternary systems XO2F:NCH:NCY and XO2F:CNH:CNY (X = P and As; Y = H and Li) as well as the corresponding binary ones were studied at the MP2/aug-cc-pVTZ level. Interestingly, the π-hole pnicogen bond in the PO2F complex is stronger than that in the AsO2F counterpart. The substituent Li in the Lewis base strengthens the hydrogen bond and pnicogen bond, but the more prominent enhancing effect is found for the pnicogen bond. The substitution effect is governed mainly through electrostatic interaction for the hydrogen bond but a combination of electrostatic and polarization interactions for the pnicogen bond. In the ternary systems, the π-hole pnicogen bond exhibits a positive cooperative effect with the hydrogen bond. Energy decomposition analysis indicates that the cooperativity is mainly attributed to the polarization energy. There is positive non-additivity between the substitution and cooperative effects, which is an effective measure for strengthening the hydrogen bond. The largest interaction energies occur in AsO2F:CNH:CNLi, amounting to -130.24 kJ/mol for the pnicogen bond and -119.90 kJ/mol for the hydrogen bond, and the former is a covalent interaction and the latter is an ion-pair hydrogen bond.
在MP2/aug-cc-pVTZ水平上研究了三元体系XO₂F:NCH:NCY和XO₂F:CNH:CNY（X = P和As；Y = H和Li）以及相应的二元体系。有趣的是，PO₂F配合物中的π-空穴氮族元素键比AsO₂F对应物中的更强。路易斯碱中的取代基Li增强了氢键和氮族元素键，但对氮族元素键的增强作用更为显著。氢键的取代效应主要通过静电相互作用控制，而氮族元素键的取代效应则是静电和极化相互作用的组合。在三元体系中，π-空穴氮族元素键与氢键表现出正协同效应。能量分解分析表明，协同性主要归因于极化能。取代效应和协同效应之间存在正非加和性，这是增强氢键的有效措施。最大的相互作用能出现在AsO₂F:CNH:CNLi中，氮族元素键为-130.24 kJ/mol，氢键为-119.90 kJ/mol，前者是共价相互作用，后者是离子对氢键。
