一个伪约翰-泰勒扭曲在一个Mo(2)(mu(2)-O)(2) 环,具有最短的Mo(IV) -Mo(IV) 双键
F Albert Cotton1, Lee M Daniels, Carlos A Murillo
1Department of Chemistry and the Laboratory for Molecular Structure and Bonding, P.O. Box 30012, Texas A&M University, College Station, TX 77842-3012, USA. cotton@tamu.edu
Journal of the American Chemical Society
|March 21, 2002
概括
研究人员合成了新的生物体化合物. 这些化合物表现出独特的Mo=Mo双键和扭曲的核心结构,由伪约翰-泰勒效应解释.
科学领域:
- 无机化学 无机化学
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
背景情况:
- 含有的边缘共享生物体化合物由于其独特的电子和结构性质而引起人们的兴趣.
- N,N'-diarylformamidine (DArF) 连接体和化乙酸或DArF组提供了多功能协调的可能性.
研究的目的:
- 为了合成和表征新型的边缘共享生物体化合物.
- 调查结构和电子特性,特别是Mo-Mo粘合和环扭曲.
- 阐明观察到的结构扭曲背后的机制.
主要方法:
- 单晶X射线衍射用于结构确定.
- 用于电子表征的光谱技术 (例如NMR,UV-Vis).
- 测量磁感应度以确认二磁性.
主要成果:
- 确定了Mo(2)(μ(2)-DArF)(2)(η(2)-L-L)))) 的四个新结构.
- 非常短的Mo-Mo距离 (2.306[2] Å) 表示一个Mo=Mo双键 (σ(2)π(2)).
- 观察到Mo-O环的显著扭曲,Mo-O键的长度不均,归因于伪约翰-泰勒效应.
结论:
- 合成的化合物表现出强大的Mo=Mo双键,与它们的二磁性相一致.
- 观察到的Mo2O2核中的C2h扭曲是关键特征,由电子因素驱动.
- 伪约翰-泰勒效应提供了一个理论框架,用于理解这些生物体象面复合体中的结构异常.
相关概念视频
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