在甲基替代双二烯的十甲基二烯复合体中,中等价值的双二烯
Corwin H Booth1, Daniel Kazhdan, Evan L Werkema
1Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. chbooth@lbl.gov
Journal of the American Chemical Society
|November 25, 2010
概括
在双二连体上的甲基替代产生多配置,在复合体中介质基态. 这些发现引入了一种新的化合物类别:中间价值 tautomers.
科学领域:
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
背景情况:
- 双 (pentamethylcyclopentadienyl) (Cp2*Yb) 复合物以其多样化的电子特性而闻名.
- 了解兰化物复合物的电子结构对于开发新材料至关重要.
- 辅助配体上的替代可以显著调整有机金属化合物的特性.
研究的目的:
- 为了研究甲基替代物对Cp2*Yb复合体中的双氨酸连接体的影响.
- 描述这些新型复合体的基本和兴奋电子状态.
- 根据它们的电子行为,为这些依特复合物建立一个新的分类.
主要方法:
- 单晶X射线衍射 (XRD) 用于结构的确定.
- 温度依赖的X射线吸收近边结构 (XANES) 和扩展的X射线吸收细结构 (EXAFS) 用于电子状态分析.
- 测量磁感应度以探测磁性质.
- 使用CASSCF-MP2计算进行理论支持的计算研究.
主要成果:
- 在Cp2*Yb.的甲基替代双氨酸复合体中建立多种配置的,中间价值基态.
- 证明甲基替代改变了基和兴奋电子状态.
- 特定的替代的识别导致多配置的,中间的性开放单元状态.
- 通过结合实验和计算数据确认中间价值行为.
结论:
- 甲基替代的Cp2*Yb的双氨酸复合体具有独特的电子结构.
- 观察到的电子配置代表了一种新的化合物类别:中间价值分离体.
- 这项工作扩大了对兰坦化有机金属化学中的电子结构调的理解.
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