Abstract

Sodium zirconium phosphate (NZP) is a potential material for immobilization of nuclear effluents. The existence
of barium containing NZP structure was determined on the basis of crystal data of solid state simulated waste
forms. The crystal chemistry of Na1−xBax/2Zr2P3O12 (x=0.1-1.0) has been investigated using general structure
analysis system programing. The barium NZP phases crystallize in the space group R-3c and Z=6. Powder
diffraction data have been subjected to Rietveld refinement to arrive at a satisfactory structural convergence of
R-factors. The unit cell volume and polyhedral (ZrO6 and PO4) distortion increase with rise in the mole % of Ba2+
in the NZP matrix. Scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray
analysis provide analytical evidence of barium in the matrix.