一个f元素酸复合物的合成,结构和磁性, (C5Me4H) 3UNOO
Nathan A Siladke1, Katie R Meihaus, Joseph W Ziller
1Department of Chemistry, University of California, Irvine, California 92627-2025, USA.
Journal of the American Chemical Society
|December 6, 2011
概括
与氧化发生反应,形成一种新型的酸复合物. 这项研究揭示了与酸连接体之间的独特结合相互作用,表明氧化的减少.
科学领域:
- 有机金属化学 有机金属化学
- 化学 的化学
- 酸复合物 酸复合物
背景情况:
- 复合物由于其独特的电子特性而引起人们的兴趣.
- 酸连接物 (NO) 可以与各种氧化状态中的金属协调.
- 对于催化和材料科学来说,了解f元素酸盐中的结合是至关重要的.
研究的目的:
- 为了合成和描述第一个f元素酸复合物.
- 为了研究酸复合体中的电子结构和结合.
- 为了探索合成复合物的反应性.
主要方法:
- 酸复合物的合成 [(C5Me4H) 3U]NO.NO.
- 用于结构确定的X射线晶体学.
- 频谱 (UV-Vis,IR,NMR) 和磁性测量. 这些测量包括光谱测量和磁性测量.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 形成第一个f元素酸复合体,[(C5Me4H) 3U]NO.NO.
- 射线晶体学揭示了一个线性U-N-O角度,但是一个短的N=O键 (1.231 Å) 和U-N键 (2.013 Å).
- 有证据表明,NO被减少为协调为U(IV的化离子 (NO-),而U(3+) 起到减少剂的作用.
- DFT计算和光谱数据证实了U 5f和NO π*轨道之间的π相互作用.
- 综合体表现出温度独立的偏磁性 (在室温下为1.36μB).
- 该复合物与Al2Me6.6形成一个附加物.
结论:
- 这项研究提出了第一个f元素酸复合体,[(C5Me4H) 3U]NO.NO.
- 这种结合的特点是5f轨道和酸 π*轨道之间存在显著的π-回结合,从而形成了U(IV) -NO-结构.
- 这种相互作用解释了观察到的线性几何和短的U-N键.
- 该综合体具有独特的磁性和反应能力.
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