Key points are not available for this paper at this time.
The A mixed-valence Y0.9Ba1.7Ca2.4Fe5O14.7 layered perovskite is obtained after topochemical oxygen insertion in Y0.9Ba1.7Ca2.4Fe5O13 under ozone flow. The crystal structure has been determined with a combination of diffraction and microscopy techniques. Mössbauer spectroscopy reveals a 5 Fe3.8+ → 2 Fe3+ + 3 Fe(4+δ)+ charge disproportionation accompanied by a smooth magnetic and electronic transition beginning at about 125 K. A layered arrangement of Fe3+ and Fe(4+δ)+ assisted by the layered character of the crystal structure is suggested. Two-dimensional magnetic interactions are detected from the magnetic behavior of the oxide and neutron diffraction experiments.
Irujo-Labalde et al. (Fri,) studied this question.