合入化,一个模型负热膨胀材料的合.
Shangye Ma1, Samuel J Baxter1, Changyong Park2
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States.
概括
三化呈现负热膨胀,在压力下结合,形成缺陷矿. 的结合使结构变硬,并改变其相变态行为,影响其量子结构相变压.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 三化 (ScF3) 是一种成熟的负热膨胀 (NTE) 材料.
- 由于横向化物振动,它在广泛的温度范围内表现出同位素NTE.
- 框架NTE材料经常经历压力诱导的相变.
研究的目的:
- 为了研究中三化的高压行为.
- 了解融入ScF3结构的形成和影响.
- 描述压力诱导的相变及其对存在的依赖.
主要方法:
- 高压X射线衍射的高压X射线.
- 气体 () 吸收和释放的测量.
- 高压中子衍射高压中子衍射
主要成果:
- 插入ScF3发生在200K以上,形成一个缺陷矿 (He_xScF3).
- 的结合使ScF3结构变硬,并改变其相变压.
- 在的存在下,立方形到圆角形的结构相位过渡在0K时转移到~0.2GPa.
结论:
- 在压力下,ScF3可以结合,形成一种新的缺陷矿结构.
- 合并显著影响了ScF3.3的结构稳定性和相位过渡行为.
- 这一发现为调整NTE材料的性质通过气体结合开辟了新的途径.
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