核性或电性胺基复合物ML (n) =PH;有什么区别?
Andreas W Ehlers1, Evert Jan Baerends, Koop Lammertsma
1Department of Chemistry, Faculty of Sciences, Vrije Universiteit, De Boelelaan 1083, NL-1081 HV Amsterdam, The Netherlands.
Journal of the American Chemical Society
|March 14, 2002
概括
密度功能研究表明,过渡金属稳定型素具有强烈的西格玛-捐赠和pi-接受特性. 配体选择显著影响它们的化学反应性和结合相互作用.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学的计算化学
- 无机化学 无机化学
背景情况:
- 素复合物是有机金属化学中的关键中间体.
- 了解它们的电子结构和反应性是设计新催化系统的关键.
- 观众连接体在调节金属结合胺的特性方面发挥着至关重要的作用.
研究的目的:
- 为了研究素过渡金属复合物的平衡结构和结合 (ML (n) =PH).
- 分析观众连接体 (L) 对素的电子性质和化学反应性的影响.
- 为了量化金属-啡相互作用中的sigma和pi键强度.
主要方法:
- 密度函数研究使用局部密度近似与非局部校正.
- 均衡结构的自相一致的计算.
- 纽带能量分析 (静电,保利排斥,轨道相互作用).
- 对称性分解用于西格玛和π键的强度估计.
主要成果:
- 具有强大的sigma-donor能力的观众连接体增强了胺基核友性.
- 具有强大的pi受体能力的配体稳定pi轨道,并增加对电子丰富物种的亲和力.
- 发现素是强大的pi受体,甚至更强的sigma捐赠体.
- 金属-芬相互作用强度增加了过渡金属组.
结论:
- 过渡金属酸的电子结构和反应性可以通过观众连接体进行调节.
- 这些复合体表现出显著的西格玛-捐赠者和pi-接受者特征.
- 金属-氨酸键在过渡金属系列中加强,影响它们的化学行为.
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