We report muon spin rotation (μSR) and neutron diffraction on the rare-earth-based magnets ${\left({\mathrm{Mo}}_{2/3}\mathrm{R}{\mathrm{E}}_{1/3}\right)}_2\mathrm{AlC}$, also predicted as parent materials for two-dimensional (2D) derivatives, where the rare earth (RE) = Nd, Gd (only μSR), Tb, Dy, Ho, and Er. By crossing information between the two techniques, we determine the magnetic moment ($m$), structure, and dynamic properties of all compounds. We find that only for RE = Nd and Gd the moments are frozen on a microsecond timescale. Out of these two, the most promising compound for a potential 2D high $m$ magnet is the Gd variant, since the parent crystals are pristine with $m=6.5\pm 0.5{\mu }_{\mathrm{B}}$, Néel temperature of $29\pm 1\mathrm{K}$, and the magnetic anisotropy between out-of- and in-plane coupling is smaller than ${10}^{-8}$. This result suggests that magnetic ordering in the Gd variant is dominated by in-plane magnetic interactions and should therefore remain stable when exfoliated into 2D sheets.

中文翻译：

---

高矩稀土基层压板的磁结构测定

我们报告了稀土基磁体的μ子自旋旋转 ( μ SR) 和中子衍射${\left({莫}_{2/3}\mathrm{电阻}{\mathrm{乙}}_{1/3}\right)}_2铝$，也预测为二维 (2D) 衍生物的母体材料，其中稀土 (RE) = Nd、Gd（仅μ SR）、Tb、Dy、Ho 和 Er。通过交叉两种技术之间的信息，我们确定磁矩（$米$)、所有化合物的结构和动态特性。我们发现仅对于 RE = Nd 和 Gd，矩在微秒时间尺度上被冻结。在这两者中，最有希望实现潜在二维高的化合物$米$ 磁铁是 Gd 变体，因为母体晶体是原始的 $米=6.5\pm 0.5{\mu }_{\mathrm{乙}}$, 尼尔温度 $29\pm 1\mathrm{钾}$，面外和面内耦合之间的磁各向异性小于 ${10}^{-8}$. 该结果表明，Gd 变体中的磁排序由面内磁相互作用主导，因此在剥离成 2D 片时应保持稳定。