在石墨烯上,Tb的低能磁性状态通常适用于石墨烯
Monirul Shaikh1, Alison Klein1, Aleksander L Wysocki1
1Department of Physics and Astronomy, University of Nebraska at Kearney, Kearney, NE 68849, United States of America.
概括
我们在石墨烯上研究了terbium (Tb) 原子,发现空心位置是首选. 电子结构和磁性属性在很大程度上取决于Tb原子的电荷状态,影响磁性异构性和稳定性.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 量子化学 是一个量子化学.
背景情况:
- 对于新型电子和磁性设备来说,了解二维材料上的 adatom 相互作用至关重要.
- 在石墨烯上的 (Tb) 原子由于Tb复杂的电子和磁性特性而形成了一个有趣的系统.
研究的目的:
- 为了研究单个 terbium adatom 在石墨烯上的电子结构和磁相互作用.
- 确定首选的吸附点,并分析不同氧化状态对磁性特性的影响.
主要方法:
- 结合密度函数理论 (DFT) 和多配置量子化学的第一原则计算.
- 包括旋转轨道合 (SOC) 来准确地建模电子和磁相互作用.
- 对各种氧化状态的分析 (Tb3+,Tb2+,Tb1+,Tb0)).
主要成果:
- 六倍对称的空洞部位被确定为Tb在石墨烯上最稳定的吸附部位.
- 在所有被调查的电荷状态中,Tb 4f 8 配置都保持不变.
- 强大的内部交换合将5d6s旋转与4f旋转对齐;由于单轴磁性异构,Tb3+和Tb2+的磁矩稳定性很高.
结论:
- 6s5d轨道的占用显著影响了石墨烯上的稀土原子的磁性异构性和稳定性.
- Tb3+和Tb2+天体表现出稳定的磁时刻,具有显著的异构性障碍,这表明潜在的自旋电子应用.
- 这项研究提供了对电子结构,自旋轨道合和2D材料上的自原子磁性质之间的相互作用的基本见解.
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