Arciniegas Jaimes Diana M, De Paoli Juan M, Nassif Vivian, Bercoff Paula G, Tirao Germán, Carbonio Raúl E, Pomiro Fernando
INFIQC (CONICET-Universidad Nacional de Córdoba), Departamento de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre esq. Medina Allende, Ciudad Universitaria, X5000HUA Córdoba, Argentina.
UGA, CNRS, Institut Néel, 38000 Grenoble, France.
Inorg Chem. 2021 Apr 5;60(7):4935-4944. doi: 10.1021/acs.inorgchem.1c00014. Epub 2021 Mar 11.
In this work, we report the synthesis as well as the structural and magnetic characterization of the three perovskites LaMnB'O (B' = Ti, Zr, and Hf). Interestingly, only LaMnTiO crystallizes in the monoclinic double perovskite space group 2/, with a complete rocksalt order of the B-site cations, whereas LaMnZrO and LaMnHfO crystallize in the orthorhombic simple perovskite space group , with complete disorder in the B site. Moreover, the magnetic susceptibility at low temperatures shows clear antiferromagnetic transitions below 10 K for the three compounds, but only the Ti-based perovskite has long-range magnetic ordering. The latter compound has an antiferromagnetic type-II structure described by the magnetic space group, while the other two have a spin-glass behavior below the transition temperature due to both spin disorder and competing superexchange interactions in the systems. This is the first time that two of the three studied compounds were synthesized (B' = Zr and Hf) and the first time that the whole series is described in thorough detail using symmetry-adapted refinements and magnetic crystallography.
在本工作中，我们报道了三种钙钛矿LaMnB'O（B' = Ti、Zr和Hf）的合成以及结构和磁性表征。有趣的是，只有LaMnTiO在单斜双钙钛矿空间群2/中结晶，B位阳离子具有完全的岩盐有序排列，而LaMnZrO和LaMnHfO在正交简单钙钛矿空间群中结晶，B位完全无序。此外，三种化合物在低温下的磁化率在10 K以下均显示出明显的反铁磁转变，但只有基于Ti的钙钛矿具有长程磁有序。后一种化合物具有由磁空间群描述的反铁磁II型结构，而其他两种在转变温度以下具有自旋玻璃行为，这是由于系统中的自旋无序和竞争的超交换相互作用所致。这是首次合成三种研究化合物中的两种（B' = Zr和Hf），也是首次使用对称适配精修和磁性晶体学对整个系列进行详细描述。
