甲基化西洛和以太的高合性相互作用:SiO键的性质
1Department of Chemistry, University of Wisconsin, Madison Wisconsin 53706, USA.
Journal of the American Chemical Society
|March 29, 2013
概括
具有令人惊的低氧基性,这是由于与氧的结合中增强了电子脱. 这种过度结合解释了它们的稳定性,并挑战了传统的结合和反应模型.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 聚合物化学 聚合物化学
背景情况:
- -氧 (Si-O) 键构成了聚合物的骨干.
- 在Si-O-Si链接中的氧原子通常表现出较低的基本性,这与基于其性的预期相反.
研究的目的:
- 调查聚合物中氧气基本性低的根本原因.
- 使用完全甲基化衍生物更准确地建模聚合物.
主要方法:
- 混合密度函数理论 (DFT) 的计算.
- 自然债券轨道 (NBO) 分析.
- 与理想化的二氧化和二甲基乙烯模型进行比较.
主要成果:
- 与C-O键相比,Si-O键中增强的超合脱局证实在甲基化中得到证实和突出.
- NBO分析显示了特定的轨道重叠,有助于Si-O-Si链接的稳定性和低基本性.
- 在同类产品中的立体扭曲并没有否定观察到的电子效应.
结论:
- 氧的低基本性归因于通过超联的显著电子移位.
- 这些发现挑战了Si-O结合和酸相互作用的离子和传统静电模型.
- 该研究提供了对聚合物的稳定性和反应性的更深入的了解.
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