Almadhi Azizah, Ji Kunlang, Injac Sean D, Ritter Clemens, Attfield J Paul
Centre for Science at Extreme Conditions (CSEC) and School of Chemistry, University of Edinburgh, Peter Guthrie Tait Road, EH9 3FD, Edinburgh, UK.
Institute Laue-Langevin, 38042, Grenoble, France.
Chem Asian J. 2024 Jul 15;19(14):e202400280. doi: 10.1002/asia.202400280. Epub 2024 Jun 11.
High pressure high temperature treatments of the composition CaMnMnTeO are found to yield only an ABB'O-type double perovskite (CaMn)MnTeO, rather than a AA'BB'O double double perovskite with A- and B- site cation order as found in analogs CaMnMnReO and CaMnMnWO with similar cation sizes. Double perovskite (CaMn)MnTeO adopts a monoclinic structure in space group P2/n with a framework of highly tilted MnO and TeO octahedra enclosing disordered Ca and Mn cations. Magnetic measurements show that (CaMn)MnTeO is a highly frustrated spin glass with a freezing transition at 5 K, and no long-range spin order is apparent by neutron diffraction at 1.6 K.
研究发现，对CaMnMnTeO成分进行高压高温处理仅生成一种ABB'O型双钙钛矿（CaMn）MnTeO，而不是像具有相似阳离子尺寸的类似物CaMnMnReO和CaMnMnWO那样具有A位和B位阳离子有序排列的AA'BB'O双钙钛矿。双钙钛矿（CaMn）MnTeO在空间群P2/n中采用单斜结构，其框架由高度倾斜的MnO和TeO八面体组成，包围着无序的Ca和Mn阳离子。磁性测量表明，（CaMn）MnTeO是一种高度受挫的自旋玻璃，在5K时发生冻结转变，在1.6K时通过中子衍射未观察到长程自旋有序。
