Incorporation of Am into the superconductor-related phase Pr2CuO4 -: art. no. 064510

Pr1.85Am.15CuO4 has been synthesized and found to have a structure consistent with the T-'-phase electron superconductors. X-ray diffraction, x-ray-absorption spectroscopy studies, and magnetic-susceptibility results are all used to conclude that Am is tetravalent in this Cu-oxide host. Despite the hole doping of the parent Pr2CuO4 compound by Am4+, magnetic measurements show that the Pr1.85Am.15CuO4 sample does not superconduct, despite the observation that a Ce-doped sample made under the same condition exhibits a diamagnetic signal at low temperatures and small applied fields. The absence of superconductivity in the Am-doped sample is discussed in terms of a magnetic model for the suppression of T-c. The presence of Am4+ in this sample precludes the formation of Am1.85Ce.15CuO4, which has been predicted to superconduct.