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一个可隔离的基离子阳离子,具有2中心3电子的π键,没有明确定义的σ键
Yanbo Mei1,2, Xiaodan Chen3, Rui Wei1
1Department of Chemistry and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen, 518055, China.
Angewandte Chemie (International ed. in English)
|November 9, 2023
概括
研究人员合成了一种新型的激素离子,在平面Si2P2环中具有罕见的2中心-3电子 (2c3e) π键. 这一突破性的发现为含有和的化合物中不寻常的结合提供了新的见解.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 量子化学 是一个量子化学.
背景情况:
- 具有2中心-3电子 (2c3e) π键的物种,缺乏底层 σ 键,是非常罕见的.
- 了解新的结合模式对于推进化学合成和材料设计至关重要.
研究的目的:
- 合成和描述一个具有2c3e π键的新基离子.
- 为了研究平面Si2P2四个成员环系统的结构和电子特性.
- 探索含有和的双环[1.1.0]基离子的类似物.
主要方法:
- 合成和分离的基离子离子盐 [K(18-C-6) ]+ {[(HCNDipp) 2Si]2P2}•−.
- 用于结构确定的X射线衍射晶体学.
- 电子偏磁共振 (EPR) 谱学用于电子表征.
- 密度函数理论 (DFT) 计算用于理论研究.
主要成果:
- 成功合成和分离了基离子盐[K(18-C-6)]+ 3•−.
- X射线结晶学证实了一个完美平面的Si2P2四个成员的环结构.
- EPR光谱和DFT计算显示,桥头P原子之间存在2c3e π键,没有明显的P-P σ键.
结论:
- 这项研究报告了第一个含Si和P的双循环[1.1.0]基离子类似物.
- 这些发现表明,这种新型无机系统中存在稳定的2c3e π键.
- 这项研究扩大了对主要组元素化学中的结合原理的理解.
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