Polytypism of BaCrO3 perovskites has been investigated at 900–1100 °C and pressures up to 22 GPa. Hexagonal 5H, 4H, and 6H perovskites are observed with increasing pressure, and the cubic 3C perovskite (a=3.99503(1) Å) is observed in bulk form for the first time at 19–22 GPa. An oxygen-deficient material with limiting composition 5H–BaCrO2.8 is synthesised at 1200 °C under ambient pressure. This contains double tetrahedral Cr4+ layers and orders antiferromagnetically below 260 K with a (0 0 1/2) magnetic structure.
Attfield, J. Paul. (2015). BaCrO3-x JSSC 2015, 2014-2015 [dataset]. University of Edinburgh School of Chemistry. http://dx.doi.org/10.7488/ds/305.