论文标题
二维二元过渡金属氮化金属$ m $ n $ _4 $（$ M $ = V，Cr，Mn，Mn，Fe，co）具有类似石墨烯的结构和强磁性
Two-dimensional binary transition metal nitride $M$N$_4$ ($M$ = V, Cr, Mn, Fe, Co) with a graphene-like structure and strong magnetic properties
论文作者
论文摘要
具有石墨烯状结构和强磁性能的二元过渡金属氮化金属很少见。根据第一原则计算，我们设计了两种$ m $ n $ _4 $（$ m $ =过渡金属）单层，它们是带有平面结构的过渡金属氮化物，由$ m $ n $ _4 $ _4 $组成。这两个结构晶格具有稳健的稳定性和与不同金属原子的良好兼容性，并且基本机制是$ sp^2 $杂交，坐标键和$π$ conjugation的组合。随着金属原子从V，CR，MN，FE转换为CO，$ M $ n $ _4 $系统的总电荷依次增加一个电子，从而导致电子和磁性的连续可调性。平面配体场是两个$ m $ n $ _4 $ lattices的另一个功能，它带来了五个3 $ d $ Metal Atom的五个亚轨道的特殊分裂，并引起了强烈的磁性。此外，通过解决Heisenberg模型与Monte Carlo方法相结合的Heisenberg模型来确定居里温度为321 K的Square-Con $ _4 $单层中的室温铁磁性。
Binary transition metal nitride with a graphene-like structure and strong magnetic properties is rare. Based on the first-principles calculations, we design two kinds of $M$N$_4$ ($M$ =transition metal) monolayers, which are transition metal nitrides with a planar structure, made up of $M$N$_4$ units aligned in the rhombic and square patterns. The two structural lattices have robust stability and good compatibility with different metal atoms, and the underlying mechanism is the combination of $sp^2$ hybridization, coordinate bond, and $π$ conjugation. With the metal atom changing from V, Cr, Mn, Fe to Co, the total charge of $M$N$_4$ system increases by one electron in turn, which results in continuous adjustability of the electronic and magnetic properties. The planar ligand field is another feature of the two $M$N$_4$ lattices, which brings about the special splitting of five suborbitals of 3$d$ metal atom and gives rise to strong magnetism. Moreover, room-temperature ferromagnetism in square-CoN$_4$ monolayer with the Curie temperatures of 321 K is determined by solving the Heisenberg model combined with Monte Carlo method.
