论文标题
单斜yfe $ _ {12} $阶段从第一原理预测
Monoclinic YFe$_{12}$ phases predicted from first principles
论文作者
论文摘要
我们使用基于遗传算法和第一原理计算的晶体结构预测技术搜索了yfe $ _ {12} $的稳定晶体结构。我们获得了两个单斜$ C2/m $结构，作为亚稳态阶段，与著名的Thmn $ _ {12} $结构不同。这两个阶段的磁性优于Thmn $ _ {12} $结构：总磁化$ m $从25.6 $μ_ {\ text {b}} $/f.u增加。最多26.8 $μ_ {\ text {b}} $/f.u。通过转换。我们还计算了这些结构在平均场近似中的这些结构的库里温度$ t _ {\ text {c}} $，并预测$ t _ {\ text {c}} $从792 k到940 k的增加，主要是由2.3--3.1的距离内的距离内的距离增加。 $ m $和$ t _ {\ text {c}} $的类似增强功能也在伪兼二进制系统y（fe $ _ {1-x} $ co $ _ {x} $ _ {x} $ _ {12} $的情况下，带有$ x $ 0-0-0.7.7。
We searched for stable crystal structures of YFe$_{12}$ using a crystal structure prediction technique based on a genetic algorithm and first-principles calculations. We obtained two monoclinic $C2/m$ structures as metastable phases that are different from the well-known ThMn$_{12}$ structure. These two phases have advantages in their magnetism over the ThMn$_{12}$ structure: The total magnetization $M$ is increased from 25.6 $μ_{\text{B}}$/f.u. up to 26.8 $μ_{\text{B}}$/f.u. by the transformations. We also calculated Curie temperature $T_{\text{C}}$ for these structures within the mean-field approximation and predicted the increase of $T_{\text{C}}$ from 792 K up to 940 K, which is mainly caused by the increase of intersite magnetic couplings within the distance of 2.3--3.1Å. The similar enhancements of $M$ and $T_{\text{C}}$ are also obtained in the pseudo-binary system Y(Fe$_{1-x}$Co$_{x}$)$_{12}$ with $x$ of 0--0.7.
