Two types of B-site ordered structures of the double perovskite Y2CrMnO6: experimental identification and first-principles study†
Abstract
Double perovskite generally exhibits small structure distortion induced by the expansion/contraction and tilting of the BO6 octahedron. It is difficult to precisely determine their structures, particularly the phase with notable pseudo-symmetry structure and two or more phases with slightly different structures. In this paper, the double perovskite Y2CrMnO6 synthesized under high pressure was studied using scanning transmission electron microscopy and first-principles calculations. The new finding is that a rock-salt ordered structure and a layer ordered structure coexist in Y2CrMnO6. Similar to the Cu2+-based compound, this Mn3+-based compound is another new system with layer ordered structure. Unlike the structures of YCrO3 and YMnO3, the ordered structure of Y2CrMnO6 displays half-metal characteristics.