σ-孔键的非共价和共价之间的过渡
1Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, United States.
The journal of physical chemistry. A
|November 9, 2023
概括
这项研究探讨了N-联体和易斯酸键,揭示了SbX5和NH3.3等某些系统的强有力的坐标共价相互作用. 其他债券,如四债券,表现出强烈的非对应性特征.
科学领域:
- * 计算化学 计算化学
- * * 化学结合理论 化学结合理论
- * 非共价相互作用
背景情况:
- * 带有σ孔的易斯酸在各种化学系统中至关重要.
- *了解由这些易斯酸形成的键的性质对于预测反应性和性质至关重要.
- *以前的研究已经探索了各种非共价相互作用,但需要对不同的易斯酸和进行系统的比较.
研究的目的:
- * 调查N-连接体 (NH3,NCH) 与含有σ孔的易斯酸之间形成的键的性质和强度.
- *根据计算的特性,将这些相互作用分类为共价或非共价.
- * 探索易斯酸结构和基核性对键强度的影响.
主要方法:
- * 用量子化学计算来研究相互作用的能量和特性.
- * 用AIM债券临界点密度的分析来评估债券性质.
- * 系统地检查了各种易斯酸 (SbX5,PX5,PX3,PbX4,SiX4,TeOX4) 和N-连接体 (NH3,NCH).
主要成果:
- * 对于五价值SbX5和PX5与NH3,以及TeOX4与NH3的强坐标共价键被确定,相互作用能量>25kcal/mol.
- *涉及PbX4的四键表现出强烈的非共价性,接近共价性.
- * 易斯酸 (SbX5 到 SbX3) 或基 (NH3 到 NCH) 的减弱导致明显的非共价相互作用.
结论:
- *N-配体和含有σ孔的易斯酸之间的键的强度和性质有很大的差异.
- * 坐标共价键受高度电友的易斯酸和强大的核友基的支持.
- *计算方法为将化学键分类为共价或非共价提供了有价值的见解.
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