SYNTHESIS AND RADIATION STABILITY OF NZP PHOSPHATES CONTAINING F-ELEMENTS

The complex phosphates Cs1+xNdxZr2-x(PO4)(3) for x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0 and the Pu phosphate NaPu2(PO4)(3) with the isotopic compositions. Pu-239 (100%) and Pu-239 + Pu-240 (similar to 20%) + Pu-238 (similar to 79%) are synthesized. The Cs, Nd, Zr phosphates were irradiated by a Co-60 gamma-source. The maximum absorbed dose was 3.10(8) Gy. X-ray diffraction and IR spectroscopy revealed no chemical and structural changes. In the Pu-239 phosphate, structural changes due to self-irradiation were not observed over a period of two years. During the irradiation, 1 mg of compound released 9.1 . 10(13) alpha-particles and formed the same amount of progeny atoms. The phase with Pu-238 became metamictized after 9.3 . 10(15) alpha-decays and the same amount of progeny atoms per 1 mg of phosphate.