Abstract: | The results of the study of Ln2(MoO4)3—Zr(MoO4)2 molybdate systems, which made it possible to obtain new double molybdates, are summarized. The specific features of phase formation in double salt systems were determined and the formation of phases with the compositions given by three formulas Ln2Zr3(MoO4)9 (Ln = La—Tb), Ln2Zr2(MoO4)7 (Ln = Sm—Y), and Ln2Zr(MoO4)5 (Ln = Tb—Lu) was established. Phase diagrams of the systems were constructed and the interrelation between the composition and the structure of the obtained phases was determined; in addition, crystallographic, thermal, and dielectric characteristics of the obtained compounds were studied. |