We present a high throughput study of the magnetic ground states for 90 transition metal dihalide monolayers TMX₂ using density functional theory based on a collection of Hubbard U values. Stable geometrical phases between 2H and 1T are first determined. Spin-polarized calculations show that 50 out of 55 magnetic TMX₂ monolayers are energetically prone to the 1T phase. Further, the magnetic ground states are determined by considering four local spin models with respect to different U values. Interestingly, 23 out of 55 TMX₂ monolayers exhibit robust magnetic ground orderings which will not be changed by the U values. Among them, NiCl₂ with a magnetic moment of 2 μ_B is a ferromagnetic (FM) insulator, while the VX₂, MnX₂ (X = Cl, Br and I), PtCl₂ and CoI₂ monolayers have noncollinear antiferromagnetic (120°-AFM) ground states with a tiny in-plane magnetic anisotropic energy, indicating flexible magnetic orientation rotation. The exchange parameters for both robust FM and 120°-AFM systems are analyzed in detail with the Heisenberg model. Our high-throughput calculations give a systematic study of the electronic and magnetic properties of TMX₂ monolayers, and these two-dimensional materials with versatile magnetic behavior may have great potential for spintronic applications.

中文翻译：

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在过渡金属二卤化物单分子层中使用 Hubbard U 校正对磁性基态进行高通量研究

我们使用基于 Hubbard U值集合的密度泛函理论，对 90 个过渡金属二卤化物单层 TMX ₂的磁性基态进行了高通量研究。首先确定 2H 和 1T 之间的稳定几何相位。自旋极化计算表明，55 个磁性 TMX ₂单层中有 50 个在能量上倾向于 1T 相。此外，通过考虑关于不同U值的四个局部自旋模型来确定磁基态。有趣的是，55 个 TMX ₂单层中有 23 个表现出稳健的磁地排序，不会被U值改变。其中，NiCl ₂磁矩为 2 μ _B的是铁磁 (FM) 绝缘体，而 VX ₂、MnX ₂ (X = Cl、Br 和 I)、PtCl ₂和 CoI ₂单层具有非共线反铁磁 (120°-AFM) 基态具有微小的平面内磁各向异性能量，表明灵活的磁定向旋转。使用 Heisenberg 模型详细分析了稳健的 FM 和 120°-AFM 系统的交换参数。_{我们的高通量计算对 TMX 2}单层的电子和磁性进行了系统研究，这些具有多种磁性的二维材料可能具有巨大的自旋电子应用潜力。