Synthesis and Rietveld structure refinement of americium pyrochlore Am2Zr2O7

The polycrystalline americium pyrochlore Am2Zr2O7 was recently synthesized from 241AmO2 and ZrO2 powders and its structure was investigated by X-ray powder pattern fitting. A Rietveld analysis was performed using the computer program JANA 2000. Am2Zr2O7 crystallizes in the space group Fd-3m with a = 10.66849(4) Å. For the less symmetrical of the two independent oxygen atoms, the unconstrained parameter x, which is characteristic of the pyrochlore structure, was found to be 0.339.