Thermal analysis of some polynuclear coordination compounds as precursors of iron garnets (M3Fe5O12, M=Y3+ or Er3+)

The thermal behaviour of four coordination compounds (NH4)(6)[Y3Fe5(C4O5H4)(6)(C4O5H3)(6)]center dot 12H(2)O, (NH4)(6)[Y3Fe5(C6O7H10)(6)(C6O7H9)(6)]center dot 8H(2)O, (NH4)(6)[Er3Fe5(C4O5H4)(6)(C4O5H3)(6)]center dot 10H(2)O and (NH4)(6)[Er3Fe5(C4O6H4)(6)(C4O6H3)(6)]center dot 22H(2)O has been studied to evaluate their suitability for garnet synthesis. The thermal decomposition and the phase composition of the resulted decomposition compounds are influenced by the nature of metallic cations (yttrium-iron or erbium-iron) and ligand anions (malate or gluconate).