黄金作为密集金中的6p元素
Guochun Yang1,2, Yanchao Wang1, Feng Peng1
1State Key Laboratory of Superhard Materials, Jilin University , Changchun 130012, China.
Journal of the American Chemical Society
|March 5, 2016
概括
高压使得金 (Au) 化合物具有前所未有的高负氧化状态. 这些新的金色表现出独特的结构和特性, 扩大了金离子的化学成分.
科学领域:
- 材料科学
- 固态化学
- 计算化学
背景情况:
- 黄金 (Au) 的负氧化状态很少见,但具有独特的特性,如铁电.
- 之前的研究只证实了单原子阳离子黄金 (Au-) 的存在.
- 黄金的较高负氧化状态仍然难以捉摸.
研究的目的:
- 探索实现更高负氧化状态的可能性.
- 在高压下研究黄金与金属的反应.
- 发现新的含金化合物,
主要方法:
- 使用了第一原则计算.
- 使用群体结构搜索来预测稳定阶段.
- 提出了高压合成条件.
主要成果:
- 在高压下预测稳定丰富的 (例如,Li4Au,Li5Au).
- 这些化合物具有独特的结构,包括Au中心的多面体和类似石墨烯的Li子网.
- 这些化合物的黄金原子具有高负氧化状态,作为6p元素.
- 在压力下与 (Cs) 等其他金属反应时,观察到类似的高负氧化状态.
结论:
- 高压是合成高负氧化状态的黄金化合物的可行方法.
- 这种方法可以创建具有新型结构图案的多种金离子.
- 这些发现为探索黄金材料的奇特性质开辟了新的途径.
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