在Cr替代的Mn4-CrAl11中,铁磁性和半金属性
M F B Noor1, K-M Law2, N Yasmin1
1Department of Physics, Astronomy, and Materials Science, Missouri State University, Springfield, MO 65897, United States of America.
概括
合成了无序的Mn-Cr-Al晶体,发现它们具有铁磁性. 密度函数理论计算表明,这些新型磁性材料中可能存在半金属性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 无机化学 无机化学
背景情况:
- 在Mn-Cr-Al系统中探索了新的磁性特性.
- 了解无序合金的结构和磁性行为至关重要.
研究的目的:
- 合成无序的Mn-Cr-Al. 的单晶.
- 描述它们的结构性,磁性和电子性质.
- 调查半金属性的可能性.
主要方法:
- 单晶合成的流量方法.
- 能量分散式X射线光谱 (EDS) 用于元素分析.
- 用X射线衍射 (XRD) 进行结构确定.
- 磁性测量 (SQUID磁力测量). 磁性测量 (SQUID磁力测量). 磁性测量 (SQUID磁力测量). 磁性测量 (SQUID磁力测量). 磁性测量 (SQUID磁力测量). 磁性测量 (SQUID磁力测量).
- 密度函数理论 (DFT) 的计算.
主要成果:
- 失序的单晶Mn4-xCr-xAl11已成功合成.
- X射线衍射证实了空间组P1 ̄的结晶,与Mn4Al11和Cr4Al11具有同结构.
- 磁性测量显示了具有低有效矩 (μeff≈1.012±0.004μB/f.u.) 的铁磁性行为. 和一个高的过渡温度.
- DFT的计算表明,在Fermi水平附近的旋转道中,有一个带隙的开放,含量增加,这表明半金属性.
结论:
- 无序的Mn-Cr-Al合金表现出有希望的铁磁性质.
- 观察到的结构和磁性特征与相关的金属间化合物一致.
- 根据DFT所指出的半金属性潜力,需要对自旋电子应用进行进一步的研究.
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