The crystal structure of LaBaCuFeO5+δ is determined by neutron powder diffraction at 15 K and the structure and magnetic properties of the La1-xPrxBaCuFeO5+δ system are studied by AC-susceptibility measurements and RT 57Fe Moessbauer spectroscopy. The best fit using the Rietveld method is obtained for an orthorhombic model in space group I mmm with unit cell parameters a = 5.5586(8) angstroms, b = 5.5550(9) angstroms and c = 7.8155(2) angstroms. The main feature of this model is a disordered structure where the oxygen atom vacancies play an important role. The magnetic susceptibility in the La1-xPrxBaCuFeO5+δ system is studied and Tf, μeff and Θ are determined. Moessbauer spectra provide information relative to the iron electronic state and environment. They support the hypothesis of the key role that the oxygen atom positions play in the magnetic properties of the system by affecting the superexchange interactions in the network.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering