在扭曲四面体几何学中的低自旋系统的解 (II)
David M Jenkins1, Angel J Di Bilio, Matthew J Allen
1Division of Chemistry and Chemical Engineering, Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|December 19, 2002
概括
这项研究引入了具有独特[PhBP(3) ]连接体的新型 (II) 复合体,揭示了伪四面体结构中的前所未有的双重基态和二面体形式中的三重基态. 这些发现提升了对复杂电子性质的理解.
科学领域:
- 协调化学 协调化学
- 有机金属化学 有机金属化学
- 无机化学 无机化学
背景情况:
- 研究双价复合物的电子和结构性质对于理解它们的反应性和潜在应用至关重要.
- 强场,阴离子三 () 素) 供体对金属中心电子配置的影响仍然是活跃研究的领域.
- 之前对具有双重基态的4坐标(II) 复合物的研究主要集中在正方形平面几何上.
研究的目的:
- 为了合成和表征具有[PhBP(3) ]配体的新型双价(II) 复合物.
- 探索由强电场产生的结构和电子现象,阳离子三 (酸) 供体连接体.
- 为了研究这些复合物的基本状态旋转配置和溶液行为.
主要方法:
- 合成 (II) 复合物与[PhBP (III) ]连接体.
- 使用X射线衍射的固态结构特征.
- 光谱分析包括SQUID,EPR和光学光谱学.
- 溶液状态研究,以确定单体/二极体平衡和旋转状态.
主要成果:
- 伪四面体 ((II) 复合物[PhBP ((3) ]CoI表现出一种罕见的双重基态.
- 模体化物和化物复合物 ([PhBP(3)]Co(mu-X))(2) 在固态中显示出三重基态,但在溶液中存在为单体低旋转物种.
- 氧化研究揭示了连接物修饰和高旋复合物的形成.
- [PhBP(3) ]联体诱导强大的联体场和轴性扭曲,有利于单体复合体中的双重基态.
结论:
- [PhBP(3) ]接体为双价复合体赋予了独特而强大的接体场,与其他素或酸盐接体不同.
- 强大的连接体场和[PhBP(3) ]连接体的轴性扭曲的结合使得在伪四面体 (II) 复合体中能够进入不寻常的双重基态.
- 这些发现扩大了对协调化学中自旋状态控制的理解,并为设计基材料提供了新的途径.
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