Synthesis and crystal structure of Ba2In – how binary are binary phase diagrams?

Ba2In crystallizes in the orthorhombic Ca2In structure type (Pnma (No. 62), a = 809.73(3) pm, b = 591.34(2) pm, c = 1093.90(4) pm, V = 532.79 cm3, Z = 4, R1 = 0.028, wR2 = 0.054). The structure can be rationalized as a hexagonal closed packing of In with occupation of all octahedral and trigonal bipyramidal holes by bariäum. A second modification as indicated in the available phase diagram could not be obtained. The presence of minor hydrogen impurities was revealed by chemical analysis and 1H NMR spectroscopy and is discussed in terms of hydride formation.