半金属铁磁性和热电效率的行为在石灰旋转 MgNi (X = S, Se):一个第一原则的方法
Ashiq Ramzan1, Mudasir Younis Sofi1, Mohammad Ishfaq-Ul-Islam2
1Department of Physics, Jamia Millia Islamia New Delhi 110025 India.
RSC advances
|July 11, 2025
概括
我们探讨了MgNi2S4和MgNi2Se4旋转子,发现它们是稳定的,半金属铁磁体,有可能用于旋转,热电和光电子应用. 这些材料在室温附近表现出极好的热电性能.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 脊柱化合物是具有多种应用的多功能材料.
- 了解电子,磁性和传输性质的相互作用对于新型设备的开发至关重要.
- MgNi2X4 (X = S, Se) 旋为先进的材料功能提供了一个尚未探索的领域.
研究的目的:
- 对MgNi2S4和MgNi2Se4螺旋进行全面的第一原则调查.
- 评估它们的结构,电子,磁,热电和光学特性.
- 评估它们适用于下一代自旋电子,热电和光电子设备的适用性.
主要方法:
- 基于密度函数理论 (DFT) 的第一原则计算.
- 用于基态测定的能量体积计算.
- 密度功能性扰动理论 (DFPT) 用于声子分散和动态稳定性.
- 用于电子结构分析的GGA和TB-mBJ函数.
- 热电性质的评估 (Seebeck系数,导电率,zT) 从100-800K.
- 分析光学特性,包括吸收,光导和介电反应.
主要成果:
- 在立方Fd-3m结构中,MgNi2S4和MgNi2Se4都是机械和动态稳定的.
- 半金属铁磁性被证实,其磁矩主要来自Ni2+离子.
- 高热电图的优点 (zT) 值 (MgNi2S4的~1.00,MgNi2Se4的~0.98) 在室温附近实现.
- 观察到显著的Seebeck系数 (高达450μV K-1) 和低的晶格导热率.
- 强烈的光学吸收,高光导率,在可见到紫外线范围内有相当大的介电反应.
结论:
- MgNi2S4和MgNi2Se4是有前途的多功能材料.
- 它们的半金属铁磁性性质非常适合用于自旋电子学.
- 优良的热电特性建议在废热回收中应用.
- 优势的光学特征表明光电子技术的潜力.
- 这些螺旋体代表了先进的下一代设备的可行候选人.
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