AI 中文总结
该研究结合扩散晶体结构生成与分层筛选的加速材料发现框架，筛选超24万种结构，识别300余种低能磁性候选物，发现4种富铁高饱和磁化强度稳定相，为磁性材料设计提供指导。
AI 中文摘要
我们提出了一种加速材料发现框架，该框架将基于扩散的晶体结构生成与分层筛选相结合，以识别同时实现高磁化强度和热力学稳定性的新型稀土-过渡金属磁体。利用该工作流程，我们系统探索了超过3000种二元（R-T）和三元（R-T-T'）组分，其中R∈{Y, Sm}，T∈{Fe, Co, Ni}，T'∈{Ti, V, Cr, Mn, Cu, Zn}，并通过机器学习原子间势预筛选和自旋极化密度泛函理论验证，过滤了约240000个生成的晶体结构。我们在密度泛函理论（DFT）水平上识别出300多个低能磁性候选物，其凸包能量在0.1 eV/原子以内，包括5个热力学稳定相。富铁二元和三元相（SmFe₁₂、YFe₁₂、YFe₁₈Ti和Sm₂Fe₁₆Mn）的最高饱和磁化强度达到约1.8 T。对称性分析表明，大多数三元候选物是已知二元原型的子群衍生物，通过Wyckoff位点分裂来容纳T'取代。位点分辨磁矩分析进一步显示，Mn与Fe亚晶格铁磁耦合，磁化强度损失极小，而Cr则反铁磁耦合，为掺杂剂选择提供了系统指导。这些发现证明了一种可推广的靶向磁性材料发现策略，并表明将生成式搜索扩展到含超过20个原子、Fe分数更高的更大晶胞，是实现饱和磁化强度超过1.8 T的稳定相的有前景途径。
英文摘要
We present an accelerated materials discovery framework that combines diffusion-based crystal structure generation with hierarchical screening to identify new rare-earth--transition-metal magnets simultaneously achieving high magnetization and thermodynamic stability. Using this workflow, we systematically explored over 3000 binary (R-T) and ternary (R-T-T$'$) compositions spanning R~$\in \{\text{Y, Sm}\}$, T~$\in \{\text{Fe, Co, Ni}\}$, and T$' \in \{\text{Ti, V, Cr, Mn, Cu, Zn}\}$, and filtered approximately 240{,}000 generated crystal structures through machine-learning interatomic potential prescreening and spin-polarized density functional theory validation. We identify 300+ low-energy magnetic candidates within 0.1~eV/atom above the convex hull at the DFT level, including 5 thermodynamically stable phases. The highest saturation magnetization reaches ${\sim}1.8$~T in Fe-rich binary and ternary phases (SmFe$_{12}$, YFe$_{12}$, YFe$_{18}$Ti and Sm$_2$Fe$_{16}$Mn). Symmetry analysis reveals that the majority of ternary candidates are subgroup derivatives of known binary prototypes through Wyckoff site splitting that accommodates T$'$ substitution. Site-resolved magnetic moment analysis further shows that Mn aligns ferromagnetically with the Fe sublattice with minimal magnetization loss, whereas Cr couples antiferromagnetically, providing systematic guidance for dopant selection. These findings demonstrate a generalizable strategy for targeted magnetic materials discovery and suggest that extending generative searches to larger unit cells ($>$20 atoms) with higher Fe fractions is a promising route toward stable phases with saturation magnetization exceeding 1.8~T.
Comments11 pages, 5 figures
