Iron orbital occupancies upon valence mixing of charge-ordered GdBaFeIIFeIIIO5

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)


Interna författare/redaktörer


Publikationens författare: J. Lindén, F. Lindroos, P. Karen
Redaktörer: Guido Langouche
Publiceringsår: 2014
Tidskrift: Hyperfine Interactions
Förläggare: Springer
Moderpublikationens namn: Proceedings of the 32nd International Conference on the Applications of the Mössbauer Effect (ICAME 2013) held in Opatija, Croatia, 1-6 September 2013
Nummer i serien: 1-3
Volym: 226
Artikelns första sida, sidnummer: 329
Artikelns sista sida, sidnummer: 339
ISSN: 0304-3843


Abstrakt

Mössbauer spectra of charge-ordered/valence-mixed GdBaFe2O5 have been analyzed in order to determine the orbital occupancies of the minority-spin d electron as a function of temperature. In the charge-ordered state below the Verwey temperature TV, it occupies the Fe2+ dxz orbital, which is ordered. Above TV, the electron partially occurs also at the trivalent iron and spreads over two additional orbitals, dx2-y2 and dz2. In the valence-mixing state (above Tp) also orbital dyz participates. The study illustrates how the Mössbauer electric-field gradient, center shift and internal field jointly reflect the distribution of the minority-spin electron culprit behind the Verwey transition.


Nyckelord

57Fe Mössbauer spectroscopy, Charge ordering, Double perovskites, Mixed valence, Valence mixing

Senast uppdaterad 2020-23-01 vid 04:19