Zeeman splitting of Mossbauer spectra of57Co doped into Eu2CuO4 and Gd2CuO4 indicates magnetic ordering of Cu moments for temperatures below about 150 K in Eu2CuO4 and below about 200 K in Gd2CuO4. © 1990 J.C. Baltzer A.G., Scientific Publishing Company.

Mössbauer spectra of57Co-doped polycrystalline or single-crystal samples of layered perovskites La2Mo4 (M=Cu, Co, Ni) and R2CuO4 (R=Nd, Eu, Gd) were recorded at room temperature and below. Of the samples studied, only La2CuO4 shows a widely separated doublet at room temperature and a single clearly resolved sextet well below TN. © 1990 J.C. Baltzer A.G. Scientific Publishing Company.