Sodium holmium double silicates with the apatite structure and compositions NaHo 9 (SiO 4 ) 6 O 2 and Na 2 Ho 8 (SiO 4 ) 6 O have been prepared by a sol-gel process and characterized by X-ray diffraction. The crystal structure of NaHo 9 (SiO 4 ) 6 O 2 has been refined, and the electrical conductivity of both compounds has been measured.
Двойные силикаты натрия и гольмия со структурой апатита состава Na2Ho8(SiO4)6O и NaHo9(SiO4)6O2 синтезированы зольгель-методом. Соединения изучены методом рентгенофазового анализа, уточнена кристаллическая структура NaHo9(SiO4)6O2, измерены электрофизические свойства.
Sodium neodymium silicate NaNd 9 (SiO 4 ) 6 O 2 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 4 f 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 Å) indicate a possible existence of luminescent properties.
