纳米氧化镁中低配位表面原子和缺陷诱导的自旋极化基态和铁磁有序
Spin-Polarized Ground States and Ferromagnetic Order Induced by Low-Coordinated Surface Atoms and Defects in Nanoscale Magnesium Oxide
摘要：
利用混合密度泛函理论研究了表面低配位原子对MgO纳米晶缺陷诱导磁性的影响。已经证明，当Mg空位被引入到立方体状MgO团簇的角部时，磁态的总能量比单重态的总能量低1-2 eV，导致自旋极化的基态。自旋密度不仅位于邻近角落Mg空位的周围O原子处，而且还沿着方向延伸到远处（1 nm或更长）的低配位表面O原子<110>。这种定向自旋离域允许远程Mg空位-Mg空位相互作用，最终导致自发的长程铁磁相互作用。
英文摘要：
We investigate the effect of low-coordinated surface atoms on the defect-induced magnetism in MgO nanocrystallites using hybrid density functional theory calculations. It has been demonstrated that when Mg vacancies are introduced at the corners of cube-like MgO clusters, a magnetic state becomes lower in total energy than the nonmagnetic singlet state by 1-2 eV, resulting in the spin-polarized ground state. The spin density is not only located at the surrounding O atoms neighbor to the corner Mg vacancy site but is also extended to the distant (1 nm or longer) low-coordinated surface O atoms along the <110> directions. This directional spin delocalization allows a remote Mg vacancy-Mg vacancyinteraction, eventually leading to a spontaneous long-range ferromagnetic interaction.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
