旋转轨道合对八面体鲁 (II/III) 和 (II/III) 复合物的还原潜力的作用
Martin Srnec1, Jakub Chalupský, Miroslav Fojta
1Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Gilead Sciences Research Center & IOCB, Flemingovo námestí 2, 166 10 Praha 6, Czech Republic.
Journal of the American Chemical Society
|July 24, 2008
概括
旋转轨道合 (SOC) 显著影响了和复合物的减少潜力. 包括SOC对于准确的计算至关重要,特别是对于 (II/III) 复合物,防止系统错误.
科学领域:
- 计算化学计算化学
- 无机化学 无机化学
- 量子化学 是一个量子化学.
背景情况:
- 对过渡金属复合物的减少潜力的准确预测对于理解它们的反应性至关重要.
- 旋转轨道合 (SOC) 是一种相对论效应,可以影响和等重元素的电子状态和性质.
研究的目的:
- 使用先进的计算方法计算各种M(2+/3+) 八面体复合体 (M = Ru, Os) 的还原潜.
- 调查和量化旋转轨道合 (SOC) 对这些减少潜力的影响.
- 评估溶解模型对计算的还原电位的精度的影响.
主要方法:
- 使用CASSCF/CASPT2/CASSI和MRCI方法,通过第一阶准退化扰动理论结合旋转轨道合 (SOC).
- 计算了由于SOC引起的M(3+) 离子的电子状态分裂.
- 根据配体大小,采用了不同的溶解模型 (明确和隐含).
主要成果:
- SOC系统地转移了减少潜力:大约. -70mV的Ru (II/III) 和大约. -300 mV的 (II/III) 复合体. -300 mV的 (II/III) 复合体.
- SOC将T(2g) 基本状态划分为克莱默斯双和四,Ru(3+) 和Os(3+) 的能量差异很大.
- 精确的降解潜力取决于溶解能量计算;对于小联体,需要明确的第二个溶解球,对于较大的联体,隐式模型就足够了.
结论:
- 旋转轨道合对于Ru和Os复合体,特别是Os (II/III) 的精确理论降解潜力至关重要.
- 如果不包括SOC,则可以导致复合物的系统错误高达300mV.
- 溶解模型的选择至关重要,并且取决于金属复合物的联体环境.
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