Crystal growth and structure of three new neodymium containing silicates: Na0.50Nd4.50(SiO4)3O, Na0.63Nd4.37(SiO4)3O0.74F0.26 and Na4.74Nd4.26(O0.52F0.48)[SiO4]4

Document Type


Subject Area(s)



Single crystals of Na0.50Nd4.50(SiO4)3O, Na0.63Nd4.37(SiO4)3O0.74F0.26, and Na4.74Nd4.26(O0.52F0.48)[SiO4]4 were synthesized via flux growth using a NaF/KF eutectic flux and the crystal structure was determined by single crystal X-ray diffraction. Na0.50Nd4.50(SiO4)3O and Na0.63Nd4.37(SiO4)3O0.74F0.26 adopt the apatite structure and crystallize in the hexagonal space group P63/m, while Na4.74Nd4.26(O0.52F0.48)[SiO4]4 crystallizes in the tetragonal space group I-4 and exhibits rare-earth mixing on the sodium site. The unit cells of the crystals are a = 9.5400(3) Å and c = 7.0331(5) Å for Na0.50Nd4.50(SiO4)3O, a = 9.5533(3) Å and c = 7.0510(4) Å for Na0.63Nd4.37(SiO4)3O0.74F0.26, and a = 12.1255(3) Å and c = 5.4656(2) Å for Na4.74Nd4.26(O0.52F0.48)[SiO4]4. These three compounds exhibit three-dimensional crystal structures that are discussed in detail in this paper.