Synthesis, structural and magnetic disordering in the IrSr2RECu2O8+x family of metalo-cuprates by HP+HT oxidation

In this work, we report the preparation of both ordered and disordered phases in the IrSr2RECu2O8 family by high pressure and high temperature oxidation. This chemical oxidation process is accompanied by a disordering of the metal sublattices of the triple perovskite cell (i.e. IrSr2RECu2O8) to an AA′ and BB′ disordered simple perovskite (Sr2RE)(Cu2Ir)O9−δ. It is especially relevant that both phases have exactly the same cation stoichiometry but different oxygen content. The disordering induced in the cation sublattices has dramatic consequences in the magnetic properties of these compounds.