Crystal Growth and Characterization of the 12L-Perovskite Ba4CeIr3O12

Highly frustrated magnetic systems are of great interest due to their exceptional properties and are topic of active research in solid state sciences. Within these systems, there are promising structures to investigate, such as perovskites with a 12L stacking sequence. The 12L-perovskites are characterized by isolated M3O12 triples of face-sharing [MO6] octahedra (“trimers”) [1]. For Ba4CeIr3O12 it is expected that for each [Ir3IVO12] trimer a total magnetic moment S ≠ 0 will result which can lead to competing intra- and inter-trimer magnetic interactions at low temperatures.      For investigation of their magnetic properties, large single crystals of Ba4CeIr3O12 are necessary. However, so far in literature only powder samples are reported [1] and no information about the phase diagram is available for this compound. With the aim of growing large single crystals of Ba4CeIr3O12 we examined the ternary system of BaO – CeO2 – IrO2 with focus on the stability of the 12L-perovskite phase. Through our investigations it was possible to grow single crystals of Ba4CeIr3O12 of up to 100 µm in size. The crystals were grown from melt solution using a BaCl2 flux and a cooling rate of 3 K/h between 1300 K and 800 K. The crystal structure was determined by X-ray diffraction and the temperature-dependent phase stability was investigated by simultaneous thermal analysis (STA).

[1] Y. Shimoda, Y. Doi, M. Wakeshima, Y. Hinatsu, Inorg. Chem. 48 (2009) 9952-9957