摩比乌斯芳香平面金属工环的观测
Ling Fung Cheung1, G Stephen Kocheril1, Joseph Czekner1
1Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States.
Journal of the American Chemical Society
|February 11, 2020
概括
研究人员发现了第一个表现出Möbius芳香性的平面单环金属激光系统. 这些-玻化物团遵循独特的电子计数规则,扩大了我们对新化学结构中的芳香度的理解.
科学领域:
- 无机化学
- 理论化学
- 物理化学
背景情况:
- 莫比乌斯的芳香度是赫克尔芳香度相反的电子计数规则的特征,最初是在扭曲的阿努尔烯中观察到的.
- 过渡金属使平面循环系统能够显示Möbius芳香度,这种现象在此类结构中以前没有被观察到.
研究的目的:
- 报告第一个表现出Möbius芳香性的平面单环金属激光系统.
- 研究-化物的结构,结合和芳香性质.
主要方法:
- 高分辨率的光电子成像用于研究集群结构和结合.
- 分析电子结构和结合特征的初始计算.
- 核独立化学转移 (NICS) 计算以评估芳香度.
主要成果:
- 合成和特征化了-玻化团ReB3和ReB4.
- ReB4-被确定为一个平面五角形环,与ReB3-的近金字塔结构不同.
- ReB4-及其中性对应体 ReB4 均表现出四个非定位的 π 电子,其中两个位于 Möbius 拓轨道.
- NICS计算证实了ReB4和ReB4的强烈芳香度,符合4n Möbius芳香度规则.
结论:
- 这项研究提供了第一个实验和理论证据,证明了平面单环金属系统中的莫比乌斯芳香性.
- 这些发现表明,-化团可以容纳Möbius芳香性,扩大了这种现象的范围.
- 这些结果验证了这些新型无机系统中Möbius芳香度的4n电子计数规则.
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