三级黄金化物:稳定和潜在超导化合物的途径
Martin Rahm1, Roald Hoffmann1, N W Ashcroft1
1Department of Chemistry and Chemical Biology and ‡Laboratory of Atomic and Solid State Physics, Cornell University Ithaca, New York 14853, United States.
Journal of the American Chemical Society
|June 20, 2017
概括
研究人员通过添加金属来发现稳定的黄金化物,从而产生半导体和金属材料. 一些化合物在压力下表现出超导性,在土替代材料中具有环境超导性的潜力.
科学领域:
- 材料科学
- 固态化学
- 超导性研究
背景情况:
- 之前发现二元黄金化物 (AuHn) 在低于300GPa的压力下理论上不稳定.
- 寻找稳定的含金化合物需要探索新的化学成分和结构.
研究的目的:
- 研究新型黄金化合物的理论稳定性和特性.
- 探索这些新材料的超导潜力,特别是在环境条件下.
主要方法:
- 使用计算材料科学方法预测各种金结构的稳定性和电子性质.
- 用密度函数理论 (DFT) 的计算来分析粘合,电子带结构和声子特性.
- 对和土金属进行了系统的替代,以调整材料的性能.
主要成果:
- 预测稳定的金二化物 (AAuH2),,和化合物显示热力学稳定性.
- 这些稳定的化合物含有AuH2分子单位,并且在1 atm处是半导体.
- 在压缩下,一些性黄金二化物形成金属,超导 AuHAu 板.
- 土替代化合物,AE(AuH2) 2,与和在1 atm时是边缘金属的.
- 这些土化合物表现出高超导过渡温度,这是由于有利的电子 - 声子合.
结论:
- 引入金属作为减少剂使黄金化物稳定,克服了以前的理论限制.
- 已经确定了具有超导性的新型半导体和金属金材料.
- 土替代提供了一个有前途的途径,以实现基于黄金的材料的环境或近环境超导性.
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