论文标题
有序以面对面的立方CR-NI合金的理论反铁磁性
Theoretical antiferromagnetism of ordered face-centered cubic Cr-Ni alloys
论文作者
论文摘要
与先前的计算相反，在半局部密度官能理论下，发现Cr-Ni合金系统的Ni富有序结构是抗磁磁性的。局部磁矩的优化显着增加了形成CRNI $ _2 $的驱动力，这是唯一的实验观察到的金属间相。这种结构的启动磁性似乎是由纵向旋转波动的海森伯格哈密顿人很好地描述的。巡回的矩矩仅由交换相互作用的强度引起。磁性在温度下的作用不太清楚，基于对实验文献的综述，特别是理论的失败，被忽视的磁相变变的存在以及反铁磁性与化学订购的偶联。每种情况都讨论了对相关商业和高渗透合金的影响。
Contrary to prior calculations, the Ni-rich ordered structures of the Cr-Ni alloy system are found to be antiferromagnetic under semi-local density-functional theory. The optimization of local magnetic moments significantly increases the driving force for the formation of CrNi$_2$, the only experimentally observed intermetallic phase. This structure's ab initio magnetism appears well described by a Heisenberg Hamiltonian with longitudinal spin fluctuations; itinerant Cr moments are induced only by the strength of exchange interactions. The role of magnetism at temperature is less clear and several scenarios are considered based on a review of experimental literature, specifically a failure of the theory, the existence of an overlooked magnetic phase transition, and the coupling of antiferromagnetism to chemical ordering. Implications for related commercial and high-entropy alloys are discussed for each case.
