四坐标铁 (I) 复合体的电子结构由一个 bis () 乙烯 () 胺连接体支
Yumiko Nakajima1, Yoshihide Nakao, Shigeyoshi Sakaki
1Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Journal of the American Chemical Society
|July 3, 2010
概括
一个新的15电子铁 (I) 复合体[FeBr (BPEP) ]被合成和特征化. 它独特的三角形单结构源于铁-子pi相互作用,揭示了高旋转的Fe (I) 中心.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 协调化学 协调化学
背景情况:
- 铁复合物在催化和材料科学中至关重要.
- 了解不同寻常的协调几何和电子结构是设计新功能分子的关键.
- 低价值铁复合物的合成和表征提供了对新型反应性和结合性的见解.
研究的目的:
- 为了合成和表征一个15电子铁复合体与一个正式的Fe (I) 中心.
- 为了阐明由此产生的复合物的结构和电子特性,[FeBr(BPEP) ].
- 为了研究金属-联结体相互作用在确定复合物的几何学中的作用.
主要方法:
- 双化物前体的单电子还原产生铁 (I) 复合体.
- 单晶X射线衍射用于结构确定.
- 用SQUID磁力测量和莫斯尔光谱学进行电子表征.
- 密度函数理论 (DFT) 计算用于电子结构分析.
主要成果:
- 成功合成了15电子铁 (I) 复合体[FeBr (BPEP) ] .
- X射线衍射揭示了铁中心周围扭曲的三角形单形几何.
- 磁力测量证实了高旋转的S = 3/2基本状态,与Fe ((I)) 一致.
- 莫斯巴乌尔光谱学和DFT计算支持高旋转Fe (I) 电子配置,并突出突出分离的分子轨道.
结论:
- 合成的铁(I) 复合体表现出一种不常见的三角形单形协调几何.
- 这种扭曲的结构归因于铁d(z(2)) 轨道和BPEP联体的pi*轨道之间的有效pi-pi相互作用.
- 这项研究为低价值铁复合物的结合和电子结构提供了宝贵的见解.
相关概念视频
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