A series of compounds with composition BaxLa1–xCoO3 (0 ≦ x ≦ 0.5) is synthesized. The rhombohedrally distorted perovskite LaCoO3 becomes cubic at x = 0.4. The electrical resistivity of the samples decreases with increasing x and the minimum lies between x = 0.2 and 0.3. The compounds with x ≧ 0.2 are ferromagnetic, but also possess a paramagnetic moment. At x = 0.5 the compound is metallic. The results can be explained by Zener double exchange as well as by Goodenough's itinerant electron ferromagnetism.

In our search for new valence-fluctuating systems, w'e have synthesized for the 6rst time the compound Eu2Ni3Si&. The powder x-ray-difraction pattern shows that the compound forms in the orthorhombic U2Co3Si5-type structure. The value of the isomer shift of the '"Eu Mossbauer resonance ( -2.8 mm/sec at 300 K) and its strong temperature dependence ( Fig. 1(a). These lines were taken as an indication of the

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