将黄金转化为"钻石":在Sr-Al-Au系统中通过三角集群相互连接的六角钻石类型Au框架的家族
Andriy Palasyuk1, Yuri Grin, Gordon J Miller
1Department of Chemistry, Iowa State University , Ames, Iowa 50011.
Journal of the American Chemical Society
|February 4, 2014
概括
研究人员发现了一系列新的金金属间化合物,具有独特的3D金原子框架. 这些材料表现出复杂的结合,从到金框架的电荷转移,揭示了新的化学相互作用.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 探索具有新型结构图案的金属间化合物对于发现新材料至关重要.
- 基于黄金的金属间金属由于其独特的电子和结构性质而引起人们的兴趣.
- --金系统代表了新化合物发现的大部分未被探索的领域.
研究的目的:
- 在Sr-Au-Al系统中发现和描述新的金属间化合物.
- 研究这些新型化合物的结构,电子和粘合特性.
- 了解和黄金在形成三维 (3-d) 四面体框架中的作用.
主要方法:
- 通过纯元素的融合合成化合物.
- 使用X射线衍射 (XRD) 进行结构确定.
- 电子结构计算 (紧密结合) 和分子中的原子量子理论 (QTAIM) 分析.
主要成果:
- 发现了四个新的同类系列的金属间化合物:SrAl3-xAu4+x,SrAl2-yAu5+y,Sr2Al2-zAu7+z,以及Sr2Al3-wAu6+w.
- 识别金原子的三维 (3-d) 四面体框架,类似于六角钻石.
- 观察[Al3]或[Al2Au]三角形取代Sr原子,形成孤立或相互连接的结构.
- 电子结构计算显示了占主导地位的Al-Au债券和从Sr向Al-Au框架的重大负担转移.
结论:
- 一系列具有3D金原子框架的新型金属间化合物已被合成和特征化.
- 这些化合物表现出复杂的化学键,涉及Al-Au相互作用和电荷转移.
- 发现的结构代表了新的类型,并扩展了已知的金基金属间化学成分.
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