Phase relations in ternary oxide systems of III and VB group elements in the subsolidus region. Ternary oxide compounds

Phase relations in the subsolidus region are considered for 54 ternary syst ems including M2O3-V2O5-R2O5, Y2O3 (La2O3, Sc2O3)-Nb2O5-Ta2O5, M2O3-B2O3-R2 O5, M2O3-Ga2O3-R2O5, Al2O3 -V2O5-R2O5,where M is a rare-earth element and R = Ta, Nb. Criteria for the formation of ternary oxide systems (size of cat ions and the ratio of the radii of ions forming the anionic part of compoun ds) are found. Crystal-chemical characteristics of MR2VO9, LaRB2O7, La4VBO1 0, Ln(7)VBO(17) (Ln = La, Pr, Nd), and La3Ga5.5R0.5O14 are presented. The v ibrational spectra of polycrystals of ternary oxide compounds and solid sol utions based on them are described in detail.