The electronic structure and magnetism of pristine magnesium oxide (MgO) (001) surface have been studied using first principle calculations based on density functional theory (DFT). Our results reveal that isolated magnesium (Mg) vacancy (V_Mg) can produce a magnetic moment of about 1.99 μ_B. The magnetic moment mainly comes from p-orbitals of oxygen atoms adjacent to V_Mg. The surface with one V_Mg will show half-metallic properties. Studies of magnetic coupling show that the surface with two V_Mg's will be in a spin singlet state (S = 0) at the distance of 2.98 or 8.42 Å between two V_Mg's, while the two V_Mg's are coupled ferromagnetically at the distance of 4.21, 5.96, or 6.66 Å. As the distance between two V_Mg's increases, the system will change from semiconductor state to half-metallic state, and finally to metal state. These findings are significant for d⁰ ferromagnetism in MgO film and useful for spintronic application.

使用基于密度泛函理论（DFT）的第一原理计算研究了原始氧化镁（MgO）（001）表面的电子结构和磁性。我们的研究结果表明，分离的镁（Mg）的空缺（V_镁）可以产生约1.99的磁矩μ_乙。磁矩主要来自与V _Mg相邻的氧原子的p轨道。具有一个V _Mg的表面将显示出半金属性能。磁耦合研究表明，具有两个V _Mg的表面在两个表面 之间的距离为2.98或8.42Å时将处于自旋单重态（S = 0）。V _Mg 's，而两个V _Mg 's以4.21、5.96或6.66Å的距离铁磁耦合。随着两个V _Mg之间的距离增加，系统将从半导体状态变为半金属状态，最后变为金属状态。这些发现对于MgO薄膜中的d ⁰铁磁性具有重要意义，对于自旋电子学应用很有用。