X-RAY-POWDER DIFFRACTION ANALYSIS OF THE ELECTRON SUPERCONDUCTOR ND2-XTHXCUO4 SYSTEM

The polycrystalline structure of the superconducting Nd2-xThxCuO4 system is studied using the X-ray diffraction technique. High-quality X-ray powder diffraction data are obtained, and analysis shows that the Nd2-xThxCuO4 compounds synthesized by solid-state reaction are well crystallized and have a body-centered tetragonal T-structure. A minor amount of Cu2O is detected, suggesting a possible Cu deficiency in the x≥0.10 compounds. A significant amount (in the 10% range) of unreacted ThO2 is also found in the x=0.25 sample, which confirms the Th solubility limit in Nd2-xThxCuO4 is 0.20. New X-ray powder diffraction data with excellent figures of merit of F30>210 and M20>260 of the superconductor Nd1.85Th0.15CuO4 and its parent compound Nd2CuO4 are reported. Values of the lattice dimensions with an estimated precision of 2.5 × 10-5 are by least-squares refinements from 32 to 33 reflections in the front reflection region.