Local structure around Fe and Cu ions in PrBaFeCuO5+delta

XANES and EXAFS measurements has been performed in the 10-300 K temperature range in order to investigate the local order around the Fe and Cu ions in two samples with different oxygen stoichiometry: PrBaCuFeO5.00 and PrBaCuF eO5.25 XANES allows determining that extra-oxygen is coordinated to the Fe ions and is not coordinated to the Cu ions. EXAFS data have been analysed i n order to obtain the temperature behaviour of the Debye-Waller factor rela ted to the oxygen surrounding the Fe and Cu ions. Additionally, low tempera ture resistivity data are reported for both samples, they show a variable r ange hoping mechanism for the conductivity. (C) 2001 Elsevier Science B.V. All rights reserved.