Valence-state mixing and separation in SmBaFe2O5+w

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A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä

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en

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Physical Review B, Volume 60, issue 22, pp. 15251-15260

Abstract

A mixed-valence state, formally denoted as Fe2.5+, is observed in the 300 K Mössbauer spectra of the most reduced samples of SmBaFe2O5+w. Upon cooling below the Verwey-type transition temperature (TV≈200K), the component assigned to Fe2.5+ separates into a high-spin Fe3+ state and an Fe2+ state with an unusually low internal field. The separation of the mixed-valence state at TV is also confirmed by magnetic susceptibility measurements and differential scanning calorimetry. A model is proposed which accounts for the variation of the amount of the mixed-valence state with the oxygen content parameter w.

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Linden, J, Karen, P, Kjekshus, A, Miettinen, J, Pietari, T & Karppinen, M 1999, 'Valence-state mixing and separation in SmBaFe2O5+w', Physical Review B, vol. 60, no. 22, pp. 15251-15260. https://doi.org/10.1103/PhysRevB.60.15251