High oxygen pressures and the stabilization of the highest oxidation states of transition metals - Mössbauer spectroscopic characterization of the induced electronic phenomena

Gérard Demazeau (1) , Alexey Baranov (2) , Igor Presniakov (2) , Alexey Sobolev (2)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Chair of Radiochemistry, Department of Chemistry

High oxygen pressures are a fruitful tool for the stabilization of the highest formal oxidation states of transition metals (Mn+) leading to the strongest chemical bonds; the improvement of the Mn+–O bond covalency induces different electronic phenomena. Among the physical characterizations applied to investigate such phenomena, 57Fe and 119Sn M¨ossbauer spectra are evaluated for studying unusual electronic configurations, orbital ordering, charge disproportionation and insulator-metal transitions in the perovskites series of 57Fe doped RENiO3 nickelates (RE = rare earths, Y and Tl) and 119Sn doped AEFeO3 ferrates (AE = Ca, Sr).

Mots clés: Oxygen pressure; High oxidation states; Mössbauer spectroscopy; Electronic configuration; Orbital ordering; Charge disproportionation; Insulator metal; Metal transition

Domaines: Matériaux

Gérard Demazeau, Alexey Baranov, Igor Presniakov, Alexey Sobolev. High oxygen pressures and the stabilization of the highest oxidation states of transition metals - Mössbauer spectroscopic characterization of the induced electronic phenomena. Zeitschrift fur Naturforschung B, 2006, 61 (12), pp.1527-1540. ⟨10.1515/znb-2006-1209⟩. ⟨hal-00119974⟩