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Fe-resonant valence band photoemission and oxygen NEXAFS study on La1-xSrxFe0.75Ni0.25O3-{delta}

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 نشر من قبل Artur Braun
 تاريخ النشر 2011
  مجال البحث فيزياء
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Iron resonant valance band photoemission spectra of Sr substituted LaFe0.75Ni0.25 O3-{delta} have been recorded across the Fe 2p - 3d absorption threshold to obtain Fe specific spectral information on the 3d projected partial density of states. Comparison with La1-xSrxFeO3 resonant VB PES literature data suggests that substitution of Fe by Ni forms electron holes which are mainly O 2p character. Substitution of La by Sr increases the hole concentration to an extent that the eg structure vanishes. The variation of the eg and t2g structures is paralleled by the changes in the electrical conductivity.

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