We report the crystal growth and the structural refinement of NaMn₇O₁₂, a manganite having a double perovskite structure. As in many similar compounds, there is coexistence of Mn³⁺ and Mn⁴⁺ but in this material they orderly occupy different sites for crystallographic reasons. Therefore, this peculiar structure can be considered as a model system for studying complex mechanisms such as charge, orbital and spin ordering. High purity bulk samples and “large” single crystals are needed to study tiny modifications in the crystallographic and magnetic structures associated to the ordering phenomena. Almost single phase (more than 96% pure) and single crystals (up to about 150 μm) of NaMn₇O₁₂ were synthesized by solid state reaction under pressure in a multi-anvil apparatus. Single crystal x-ray diffraction and SEM analysis have been used to characterize the crystals. The structure refinement indicates that NaMn₇O₁₂ crystallizes in the cubic Im3 space group, with a = 7.312 Å and Z = 2. Further studies are in progress to optimize the synthesis conditions, in order to grow larger crystals.

---

The full text of this paper in pdf-Format:

If you have come directly to this page, click this symbol to go to the CRT homepage.