Phase Relations in the Systems A2O‐Metal Oxide‐WO3 (A=Li, Na; Metal=Fe, Cr, Sn, Zr, Th, V)

Abstract

Phase relations, with special emphasis on the formation of wolframite‐type phases, were determined in 12 ternary systems, each containing an alkali oxide (Li2O, Na2O), a polyvalent oxide (Fe2O3, Cr2O3, SnO2, ThO2, ZrO2, V2O5), and WO3. Among 12 ternary phases characterized, 5 have the wolframite‐type structure. They are LiFe(WO4)2, LiCr(WO4)2, NaFe(WO4)2, NaCr(WO4)2, and Li2Zr(WO4)3. Complete series of solid solutions exist along Li(Fe,Cr) (WO4)2 and Na(Fe,Cr)(WO4)2 joins but not along other wolframite joins. Both LiFe(WO4)2 and LiCr(WO4)2 were also found to form complete solid solution series with MgWO4, a compound used hi this study to represent the simple wolframite‐type phase.