The structure and luminescent properties of Mn0.5Zr2(PO4)3

The phosphate Mn0.5Zr2(PO4)3 can be obtained at high temperature (1400°C). It crystallizes in the rhombohedral system (space group R3̄) with parameters ah = 8.85(1) and ch = 21.80(5) Å in the equivalent hexagonal cell. Its structure, determined by the Rietveld method, is typical of the Nasicon-type arrangement with a partial occupation of the two M(1) sites [(3a) and (3b)] generated by the space group. The magnetic and luminescent properties are consistent with the crystallographic data and give evidence of the existence of a small amount of Mn3+ in such as-prepared samples, the actual composition being Mn2+0.5–xMn3+2x/3Zr2(PO4)3 with x ≅ 0.03.