Thermal decomposition of Y,La and lanthanide benzene-1,2-dioxyacetates in an air atmosphere

The thermal decompositions of Y, La and lanthanide (from Ce(III) to Lu(III) benzene-1,2-dioxyacetates with general formula Ln₂(C₁₀H₈O₆)₃·nH₂O were studied. The hydrated complexes first lose water of crystallization in one or two steps to yield anhydrous compounds or hydrates containing coordination water molecules, and then decompose to the oxides Ln₂O₃, CeO₂, Pr₆O₁₁ and Tb₄O₇ with formation of intermediates, carbonates and oxycarbonates (La, Pr-Eu), oxycarbonates (Y, Tb-Lu) or carbonate (Gd) only. Anhydrous cerium(III) benzene-1,2-dioxyacetate decomposes on heating directly to CeO₂.