作为新合成子的双重中心对称Si···π四环键――来自晶体结构和DFT计算的证据
Mohammad Aarabi1, Samira Gholami1, Sławomir J Grabowski2,3
1Department of Chemistry, University of Isfahan, Isfahan 81746-73441, Iran.
The journal of physical chemistry. A
|November 17, 2023
概括
这项研究揭示了 bis (((μ2-ethynylsilyloxo) -dichloro-aluminum) (BEDCA) 模体中的四键是弱的,并且在某些方法中无法检测到. 然而,在相关复合体中也观察到具有共价特性的强试验键.
科学领域:
- 晶体工程 晶体工程
- 超分子化学 超分子化学
- 计算化学是一种计算化学.
背景情况:
- 环键越来越被认为是晶体结构中重要的非共价相互作用.
- 在像BEDCA这样的有机化合物中,环键的特殊作用仍未得到充分研究.
- 了解这些相互作用对于设计具有定制性质的新材料至关重要.
研究的目的:
- 为了研究 bis () (BEDCA) 和相关分子二次体中的四键的存在和性质.
- 从理论上分析Si··π四键的特征,并将它们与三键进行比较.
- 评估不同计算方法在检测这些非共价相互作用方面的性能.
主要方法:
- 使用 ωB97XD/aug-cc-pVTZ 的密度函数理论 (DFT) 计算.
- 使用分子中的原子量子理论 (QTAIM) 进行分析.
- 自然键轨道 (NBO) 分析,能量分解分析 (EDA) 和非共价相互作用 (NCI) 方法.
主要成果:
- 在BEDCA和模型系统中确定了由两个等价的Si···π四键连接的中心对称二次体.
- 发现四键是弱的,并不是通过包括QTAIM在内的所有计算方法一致检测到的.
- 在一些研究的复合体中观察到强大的试验键,表现出共价特征.
结论:
- 这些系统中的四键是弱相互作用,其检测依赖于方法.
- 试验键代表了一种显著而强烈的相互作用,接近共价键强度.
- 这些发现提供了关于控制有机结构组装的非共价相互作用的见解.
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