Phase diagram of the Ba3Y(PO4)3-BaRbPO4 system and solid solutions with α-BaRbPO4 structure in the quasi-ternary system YPO4-Rb3PO4-Ba3(PO4)2

The concentration ranges in which the high-temperature solid solution with the α-BaRbPO4 structure forms in the quasi-ternary YPO4-Rb3PO4-Ba3(PO4)2 system have been determined. The formation probability of this solution is related to the structure similarity of the initial phosphates constituting this phase.