Double Molybdates and Tungstates of the Rare Earth and Alkali Metals

Data on the preparation, structure, and various properties of the double tungstates and molybdates (EO₄) of the alkali (M) and rare earth (R) metals with the composition RM(EO₄)₂ have been summarised and systematised. The regular features of the change in the symmetry, polymorphism, and nature of the fusion with change in the nature of the alkali and rare earth metals have been examined. The bibliography contains 82 references.