在金属玻璃中长距离的拓秩序
Qiaoshi Zeng1, Hongwei Sheng, Yang Ding
1International Center for New-Structured Materials, Zhejiang University, Hangzhou 310027, People's Republic of China.
Science (New York, N.Y.)
|June 18, 2011
概括
金属玻璃展示了隐藏的远程订单. 在高压下,Ce75) Al25) 金属玻璃转化为单晶,揭示了其底层的拓结构.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 晶体学 晶体学是指结晶学.
背景情况:
- 晶体具有远程周期性原子序,与金属玻璃等无形材料不同.
- 75) 25) 金属玻璃以前被认为是结构无形和同otropic.
研究的目的:
- 为了调查Ce(75) Al(25) 金属玻璃中隐藏的结构秩序.
- 要了解这种金属玻璃中压力诱导结晶的机制.
主要方法:
- 高压实验使用高达25千兆帕斯卡尔的水静压.
- 结构分析的同步射线X射线衍射技术.
- 分子动力学模拟以建模原子行为.
主要成果:
- 虽然Ce75) Al25) 金属玻璃看起来是无形的,但它具有远程拓秩序.
- 在高压下,金属玻璃转化为单面中心立方 (fcc) 晶体,具有均的方向.
- Ce和Al之间的原子大小不匹配阻碍了结晶,但拓秩序仍然存在.
结论:
- 在Ce(75) Al(25) 金属玻璃中存在一个长距离的fcc拓顺序,被原子不匹配掩盖.
- 在中,压力诱导的电子转换消除了原子不匹配,使得拓秩序能够表现为单晶.
相关概念视频
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