Synthesis and study of NaNd9 (SiO4)6O2

Sodium neodymium silicate NaNd9(SiO4)6O2 with the apatite structure has been synthesized and studied by X-ray diffraction and scanning electron microscopy. No sodium oxide sublimation occurred during ceramic synthesis by the selected method. The Rietveld method shows that sodium atoms in the structure are ordered (in the 4f position). The O(4) oxygen atoms, which are not involved in silicate ions, are positioned in the centers of triangles formed by Nd(2) atoms. Rather long Nd-Nd distances (3.940 A) indicate a possible existence of luminescent properties.