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Magnetic and magnetotransport measurements have been used to study the compositional dependence of the electronic properties of the solid solutions and . It was found that these compounds are ferromagnets and have the rhombohedrally or orthorhombically distorted perovskite structure. The substitution of Pb ions by Cd leads to the transition from the metallic to the insulating state. The intermediate compositions exhibit two peaks of the resistivity and magnetoresistance. The high-temperature peak is associated with the Curie temperature whereas there is no magnetic anomaly in the temperature interval of the second peak. We suppose that Cd ions participate in the formation of the narrow impurity band limiting the mobility of charge carriers.

Whilesubstituting La3+ ions by Ca2+ ions in solid solutions with La3: Ca (MnlmxMnx )03 perovskite structure the antiferromagnetic-ferromagnetic transition occurs I l l . According to 111 in the O.lSx50.2 range of transition from

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