在正方形铜化物中巨大的负线性压缩性
Swayam Kesari1, Alka B Garg2,3, Nilesh P Salke1,4
1Bhabha Atomic Research Centre, Solid State Physics Division, Mumbai 400085, India.
Physical review letters
|April 11, 2025
概括
研究人员在广泛的压力范围内在低温铜化物 (LT-CuCN) 中发现了巨大的负线性压缩性 (NLC). 这一发现为具有独特机械反应的材料提供了新的可能性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 负线性压缩性 (NLC) 是一种罕见的现象,在液压压力下,材料在一个维度内收缩.
- 现有的NLC材料通常显示有限的NLC大小或在狭窄的压力范围内运行.
研究的目的:
- 在新材料中报道巨型NLC的发现.
- 调查NLC及其潜在机制的压力和温度依赖性.
主要方法:
- 高压X射线衍射 (XRD) 研究以测量压力下的结构变化.
- 可变温度和压力拉曼光谱检测声子动态.
主要成果:
- 在环境条件下在LT-CuCN中沿a轴观测到 -20.5 TPa-1的巨型NLC.
- CN的正方形相保持稳定,达到9.8 GPa.
- 确定了与NLC和负热膨胀 (NTE) 相关的特定声子振动.
结论:
- 在一个扩展的压力范围内,LT-CuCN表现出前所未有的巨型NLC.
- 音频模式被证实是本文中NLC和NTE的起源.
- 这一发现为设计具有可调节压缩性的材料开辟了道路.
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