RT Journal Article T1 Mössbauer study of the (Ru1-xFex)Sr2GdCu2O8-δsystem and two of its possible impurities: SrRuO3and Gd2CuO4 A1 Gómez, R. A1 Marquina, V. A1 Arévalo López, Ángel M. A1 Pérez, J. L. A1 Ridaura, R. A1 Marquina, M.L. A1 Escamilla, R. A1 Akachi, T. AB Mössbauer spectra of a series of samples of the weak ferromagnetic (Ru1-xFex)Sr2GdCu2O8-δ system reveal the existence of three dissimilar sites where the Fe atoms cango into the structure. The Mössbauer parameters of the three observed quadrupole doublets, together with the relative population on each site, allow the following site assignment for the iron atoms: Fe3+ in four-fold planar coordination at Ru sites; Fe3+ in five-fold pyramidal coordination also at Ru sites and Fe2+ or Fe3+ in five-fold coordination at Cu sites. This assignment implies the formation of oxygen-vacancies at the charge reservoir (the RuO2 planes) that affect the structure and the superconducting and magnetic properties of the undoped system. Moreover, a close correlation between the oxygen content, calculated through the Mössbauer data, and the measured cell volume is established. We also report the Mössbauer spectra of two compounds (SrRu0.95Fe0.05O3 and Gd2Cu0.95Fe0.05O4) that could be formed as impurities during the synthesis of our samples. PB Springer Verlag SN 0304-3843 YR 2006 FD 2006 LK https://hdl.handle.net/20.500.14352/53018 UL https://hdl.handle.net/20.500.14352/53018 LA spa DS Docta Complutense RD 6 abr 2025