具有NiAs型结构的MnN高压相的高压合成
Shuto Asano1, Ken Niwa1,2, Keith V Lawler3
1Department of Materials Physics, Graduate School of Engineering, Nagoya University, Nagoya, Aichi 464-8603, Japan.
Inorganic chemistry
|November 22, 2023
概括
在高压下合成了一种新的NiAs类型的 mononitride (MnN) 阶段. 这种可逆相位过渡发生在55GPa以上的扭曲的NaCl型结构中.
科学领域:
- 材料科学 材料科学 材料科学
- 高压物理 高压物理
- 固态化学 固态化学
背景情况:
- 单化物 (MnN) 在不同的条件下表现出复杂的结构性行为.
- 了解过渡金属化物中的相变对于材料开发至关重要.
研究的目的:
- 为了合成和表征一种新的高压阶段的 mononitride.
- 为了研究MnN的压力诱导的结构相变.
主要方法:
- 使用激光加热的钻石天细胞进行高压合成.
- 通过施加压力和减压来表征结构阶段过渡.
主要成果:
- 一个NiAs类型的MnN相在大约55GPa以上的压力下成功合成.
- 从四角形扭曲的NaCl型MnN过渡到NiAs型MnN的过渡在解压时是可逆的.
- 与扭曲的NaCl类型相相相比,NiAs类型的MnN具有更高的密度和散量模量.
结论:
- 这项研究报告了第一个从扭曲的NaCl类型到NiAs类型的结构相变的化物.
- 在MnN中观察到的相位过渡压力低于类似氧化物,可能是由于反铁磁排序效应.
- 过渡的可逆性和NiAs类型相的特性为在极端条件下的化物材料行为提供了洞察力.
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