基于50个RF3-R'F3 (R=La-Lu) 系统中的相变型机制的负热膨胀的两组件稀土化物材料
Boris P Sobolev1, Elena A Sulyanova1
1Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences, Leninskiy Prospekt 59, 119333 Moscow, Russia.
International journal of molecular sciences
|September 28, 2023
概括
在R'F3-RF3系统中预测了通过相变 (NTE-II) 呈现负热膨胀 (NTE) 的新化物质. 这些材料具有可调节的特性和巨大的NTE效应,超过现有的NTE材料.
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:
- 负热膨胀 (NTE) 材料对于需要维度稳定的先进应用至关重要.
- 阶段过渡型NTE (NTE-II) 机制提供了显著的体积变化,但需要仔细的材料设计.
- RF3-R'F3系统为发现新型NTE-II材料提供了一个有希望的途径.
研究的目的:
- 在105个R'F3-RF3系统中预测NTE-II材料的形成.
- 探索多态变换 (PolTrs) 和密度异常在NTE-II.II中的作用.
- 建立化学分类 (ChCl) 用于对NTE-II化物材料进行系统的搜索.
主要方法:
- 基于相位图的R'F3-RF3系统中NTE-II形成的计算预测.
- 在R'F3化合物中分析多态转换 (PolTrs),重点关注密度异常.
- 为材料发现开发化学分类 (ChCl) 和系统类型 (TypeS).
主要成果:
- 在R'F3-RF3系统中的十种系统类型中,NTE-II材料的预测形成在四种系统中.
- 在双相复合材料 (α + β) 中确定了巨大的NTE效应 (高达4.7%的体积变化).
- 建立了一个广泛的调节范围,用于从-148到1186±10°C的平均体积变化 (ΔV/Vav).
结论:
- R'F3-RF3系统是新型NTE-II化物材料的丰富来源,具有可调节的特性.
- 开发的化学分类和系统类型化有助于有效地发现这些材料.
- 与现有的NTE-II材料相比,预测的NTE-II化物材料表现出优越的性能.
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