同原子恒星四角形[Tl8]6-在Cs18Tl8O6中,旋转轨道合的相互作用,以及Jahn-Teller扭曲
Ulrich Wedig1, Vyacheslav Saltykov, Jürgen Nuss
1Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany.
Journal of the American Chemical Society
|August 14, 2010
概括
一种新型的氧化,Cs(18) Tl(8) O(6),被合成并进行了表征. 相对论计算显示其二磁性源于自旋轨道合影响[Tl(8)](6-) 四面体星团离子.
科学领域:
- 固态化学 固态化学
- 无机合成 无机合成
- 计算材料科学 计算材料科学
背景情况:
- 和氧化物是复杂结构的化合物的一类.
- 了解集群离子的电子结构对于预测材料性质至关重要.
- 之前的研究已经确定了具有不同几何形状的异电子集群,如Cs{8}Tl{8}O.
研究的目的:
- 为了合成和描述新型化合物Cs(18)Tl(8)O(6).
- 为了研究Cs{18) }Tl{8} O{6}中的[Tl{8} }8} O{6}集群离子的电子结构.
- 阐明旋转轨道合在观察到的二磁性行为中的作用.
主要方法:
- 从二进制CsTl和Cs(2) O. 6中合成Cs(18) Tl(8) O(6).
- 单晶X射线衍射用于结构确定.
- 相对论密度函数理论 (DFT) 的计算,包括旋转轨道合.
主要成果:
- Cs(18) Tl(8) O(6) 在一个新的立方体结构 (空间组I23) 中结晶.
- 该化合物含有四面体的星形[Tl(8) ](6-) 集群离子.
- 尺度相对论计算表明一个开放系统,但旋转轨道合计算显示了一个封闭电子结构,与二磁性相一致.
结论:
- Cs{18) Tl{8} O{6} 的二磁性是[Tl{8} 6-) 星团上自旋轨道合效应的直接结果.
- 与之前观察到的平行形星团相比,四面体星团代表了一个新的结构动机.
- 相对论效应对于准确描述这种重元素系统的电子性质至关重要.
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