Mechanism and Functionality of Pnictogen Dual Aromaticity in Pentazolate Crystals
Mechanism and Functionality of Pnictogen Dual Aromaticity in Pentazolate Crystals
复制标题
五唑盐晶体中磷元素双芳香性的机理和功能
DOI：
10.1002/cphc.201900674
复制
发表时间：
2019
期刊：
影响因子：
2.9
通讯作者：
Chen Jun
中科院分区：
文献类型：
--
作者：
Zhang Lei;Yao Chuang;Yu Yi;Wang Xing;Sun Chang Q.;Chen Jun
Our recent work (J. Phys. Chem. Lett.2019,10, 2378) reported the discovery of the abnormal pnictogen dual aromaticity (π and σ) incyclo‐N5−, which makes the anion unstable in nature but confers enhanced stability in sufficiently acid solution. Herein, we present systematic quantum calculations on the structures, energetics and dynamics of the pentazolate salt and metal pentazolate hydrates, focusing on the mechanism and functionality of the pnictogen dual aromaticity in these crystals, which are verified by experiments. We find that owning a net charge of −eis crucial to the formation of the dual aromaticity and the stabilization of thecyclo‐N5−. The competition between the dual aromaticity and the proton affinity drives thecyclo‐N5−to be unreactive to acid and remain unprotonated in these crystals. We decompose the crystal packing effect into pure mechanical compression and interspecies nonbonding interactions, and figure out that the type and number of the adjacent counterions of thecyclo‐N5−anion, instead of the compression effect, accounts for the protonation state reversion in the vacuum and in the crystal. The current work supports our original conclusion (Science2018,359, eaas8953) and is expected to provide compelling evidence against the current debate on thecyclo‐N5−stability (Science2018,359, eaao3672;J. Phys. Chem. Lett.2018,9, 7137;J. Am. Chem. Soc.2019,141, 2984).
