Thermal expansion, electrotransport and magnetic properties of layered barium-yttrium ferrocuprate with cation deficiency

The cationic nonstoichiometry effect on the structure, thermal expansion, electrical conductivity, thermo-EMF and magnetic susceptibility of yttrium-barium ferrocuprate has been studied. It has been found that unit cell parameters of YBaCuFeO5+d phase remained virtually unchanged upon formation of 5% vacancies in different cationic sublattices (Y, Ba, Cu/Fe) of its structure. The linear thermal expansion coefficient value of YBaCuFeO5+d derivatives decreases with formation of vacancies in its A-sublattice (Y, Ba). The Neel temperature of YBaCuFeO5+d increases with formation of iron vacancies and decreases with formation of copper vacancies in its structure. (authors)