The Crystal Structure and Ionic Conductivity of the Ilmenite Polymorph of NaSbO3

Abstract Single crystals of NaSbO 3 with the ilmenite structure have been grown. The crystal structure has been determined by single crytal X-ray diffraction measurement. The ilmenite phase of NaSbO 3 crystallizes in the trigonal system with hexagonal symmetry, space group R3 (No. 148), and Z = 6. The hexagonal unit cell parameters are a = 5.2901(3) A, c = 15.926(2) A, and V = 385.98(4) A 3 . The structure of ilmenite NaSbO 3 is built up from layers of edge-sharing SbO 6 octahedra with sodium ions located between the layers in octahedral sites. The ionic conductivity of the ilmenite analog of NaSbO 3 was investigated by ac complex impedance measurements and the results are discussed in terms of the structural dimensionality, the Na + -oxygen bond strength, the sodium occupancy, and the bottleneck size.