On the magnetic properties and the phase composition of the Cr 2 O 3 MnO x ‐system (2 ≥ x ≥ 1.5)

The mixed oxide system Cr 2 O 3 MnO x (2 ≥ x ≥ 1.5) was investigated by X‐ray diffraction, by measurements of magnetic susceptibility, and by chemical determination of excess oxygen (B UNSEN'S method). The Presence of the antiferromagnetic oxides Cr 2 O 3 , β‐MnO 2 , α‐Mn 2 O 3 and a ferromagnetic phase Cr 1−y Mn y O 2 was stated. The formation of the latter with fourvalent chromium is explained by a lattice induction effect of the MnO 2 (rutile type).