一个Fe (VI) bis (imido) 复合物的结构和光谱特征
Jorge L Martinez1, Sean A Lutz1, Hao Yang2
1Department of Chemistry, Indiana University, Bloomington, IN 47405, USA.
Science (New York, N.Y.)
|October 16, 2020
概括
研究人员合成了一种稳定的六价铁 (Fe(VI)) 复合物,这是一个罕见的氧化状态. 这种具有独特摇摆几何的Fe (VI) 化合物使用先进的光谱和结构方法进行了表征.
科学领域:
- 无机化学
- 生物有机化学
- 协调化学
背景情况:
- 高价铁物种在生物氧化反应中至关重要.
- 六价铁复合物,不包括铁酸盐,在化学中非常罕见.
- 了解这些物种可以了解氧化生物机制.
研究的目的:
- 合成和表征一个稳定的六价铁 (Fe(VI)) 复合物.
- 研究Fe (V) 和Fe (VI) bis (imido) 复合物的结构和电子特性.
- 阐明这些铁复合体中观察到的独特几何结构的因素.
主要方法:
- 通过单电子氧化合成Fe (V) 和Fe (VI) bis (imido) 复合物.
- 单晶X射线衍射用于结构确定.
- 斯尔,X射线光电子光谱 (XPS),X射线吸收光谱 (XAS) 和电子核双共振 (ENDOR) 用于电子特征.
- 计算电子结构计算.
主要成果:
- 一个稳定的Fe(VI) 复合物 (3) 从Fe(V) 前体 (2) 中成功合成.
- 两个Fe (V) 和Fe (VI) 复合体都表现出一种罕见的四坐标铁中心,具有独特的"摇摆"几何形状.
- 光谱数据和计算证实了2的低旋转d3Fe(V) 配置 (S=1/2) 和3的二磁性d2Fe(VI) 配置 (S=0).
- 观察到的摇摆几何归因于Fe-imido sigma和pi结合相互作用的相互作用.
结论:
- 可以通过控制氧化低价铁前体来制备稳定的Fe ((VI) 复合物.
- 这种"摇摆"的几何是这些铁复合体中反复出现的结构图案,是由电子因素决定的.
- 这项工作扩展了已知的高价值铁的化学成分,为其电子结构和结合提供了洞察力.
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