Phase equilibria in the system Rb3PO4–Ba3(PO4)2

• Published in: Journal of thermal analysis and calorimetry Vol. 103; no. 2; pp. 761 - 766
• Main Authors: Radomińska, E., Znamierowska, T., Szuszkiewicz, W.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.02.2011; Springer
• Subjects: Analytical Chemistry; Chemistry; Chemistry and Materials Science; Conversion; Diffraction; Exact sciences and technology; General and physical chemistry; Inductively coupled plasma; Inorganic Chemistry; Measurement Science and Instrumentation; Melts; Oxides; Phase diagrams; Phase equilibria; Physical Chemistry; Polymer Sciences; Rubidium; Vaporization; Rubidium and barium orthophosphates; BaRbPO; Phase diagram; X-ray powder diffraction; Infrared spectrometry; Fourier transformation; Rubidium Phosphates; Thermogravimetry; Barium Phosphates; Thermal analysis; X ray diffraction; Phase equilibrium
• ISSN: 1388-6150; 1572-8943
• DOI: 10.1007/s10973-010-0962-y

The system Rb 3 PO 4 –Ba 3 (PO 4 ) 2 was investigated by thermoanalytical methods, X-ray powder diffraction, ICP, and FT-IR. On the basis of the obtained results its phase diagram was proposed. For this system with one intermediate compound, BaRbPO 4 , we found that this compound melts congruently at 1700 °C, exhibits a polymorphic transition at 1195 °C and is high-temperature unstable. Also, the intermediate compound was subject to gradual decomposes to Ba 3 (PO 4 ) 2 (the solid phase) and vaporization (with conversion of phosphorus and rubidium oxides into vapor phase). We also found that Rb 3 PO 4 melts congruently at 1450 °C and shows a polymorphic transition at 1040 °C. Regarding Ba 3 (PO 4 ) 2 , we have confirmed that it melts congruently at 1605 °C and exhibits a polymorphic transition at 1360 °C.