At high temperatures Sr2MnO4-y crystallizes in the K2NiF4 structure with anion defects. X -ray structure determination in space group I 4/m m m (No. 139) with a = 380.58(3), c = 1253.19(11) pm reveals the composition Sr2MnO3.84±0.05 for a single crystal prepared under argon at 1510 °C. The oxygen deficiency is restricted to the basal oxygen atoms in the perovskite layer. The X -ray experiment shows a statistical distribution of the defects. They lead to a distorted tetragonal pyramidal coordination of the Mn3+ ions.
Zeitschrift für Naturforschung B is an international scientific journal which publishes original papers, microreviews, and letters from all areas of inorganic chemistry, solid state chemistry, coordination chemistry, molecular chemistry, and organic chemistry.