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目前的芳香度概念的极限

Amnon Stanger¹, Jordi Poater^2,3, Yirong Mo⁴

¹Schlich Department of Chemistry, Technion, Haifa 3200003, Israel. stanger@technion.ac.il.

Physical chemistry chemical physics : PCCP

|January 21, 2026

概括

在具有较重元素的循环系统中评估芳香度具有挑战性. 不同的评估芳香度的方法显示出不良的相关性,质疑其在第二行之外的存在.

科学领域:

量子化学是一个量子化学.
理论化学理论化学
芳香性研究芳香性研究

背景情况:

芳香性是化学的一个基本概念,传统上定义为循环,平面系统与非定位的pi电子.
将芳香度的理解扩展到涉及更重元素的系统 (超越第二行) 提出了重大的理论挑战.

研究的目的:

研究和比较不同的方法来评估周期性pi电子系统中的芳香度.
对含有第二,第三和第四行元素的系统评估已建立的芳香度标准的适用性和可靠性.

主要方法:

采用了三种不同的方法来评估芳香度:磁性 (NICS变体,电流密度分析),基于电子密度 (MCI,MCIπ指数) 和能量 (Bond-Length-Valence (BLW) 方法).
将这些方法应用于15个循环2π电子系统和9个6π电子带电和中性系统.

主要成果:

从磁性,电子密度和能量标准获得的芳香度排名中观察到显著的分歧.
不同的芳香度评估方法之间没有明确的相关性.
结果表明,NICS值应谨慎解释,而不是作为芳香度的唯一决定因素.

结论:

各种芳香度指标之间缺乏相关性,凸显了定义和量化第二行以外的系统芳香度的内在困难.
将传统标准应用于较重的同源元素的不一致性引发了关于第二行以外元素中芳香性存在的根本问题.
需要进一步的研究来解决关于周期表中芳香度的普遍性的悬而未决的问题.

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