Regularities of the Changes in the Physicochemical Properties in the Series of Me0.5Ln0.5Nb2O6 Compounds (Me = Li or Na and Ln = Nd–Lu)

The symmetry of Me0.5Ln0.5Nb2O6 crystals (Me = Li or Na and Ln = Nd–Lu) is refined using X-ray diffraction and optical methods. The lattice parameters of the crystals are determined. The regularities of the changes in the crystal system, the lattice parameters, and the unit cell volume in a series of Me0.5Ln0.5Nb2O6 compounds with variations in the atomic number of the rare-earth element are revealed.