% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@INPROCEEDINGS{Schmitz:281650,
      author       = {Schmitz, D. and Schmitz-Antoniak, C. and Warland, A. and
                      Darbandi, M. and Haldar, S. and Bhandary, S. and Eriksson,
                      O. and Sanyal, B. and Wende, H.},
      title        = {{H}uge intra-atomic dipole moment of the iron spin-density
                      in the low temperature phase of magnetite},
      reportid     = {FZJ-2016-01338},
      year         = {2015},
      abstract     = {Magnetite nanoparticles (NPs) with 6 nm diameter and a 200
                      nm thick magnetite reference film were studied with a
                      combination of experimental and theoretical methods, i.e.
                      x-ray absorption near edge spectroscopy (XANES), x-ray
                      magnetic circular dichroism (XMCD), vibrating sample
                      magnetometry (VSM) and electronic structure calculations
                      based on density functional theory. For the NPs, increases
                      of the white line intensity and the XMCD signal with
                      increasing temperature were observed between 50 K and 100 K
                      (Fig. 1a, b). A similar increase of the XMCD signal was also
                      observed for the film between 125 K and 175 K, which is
                      above its Verwey transition temperature of 120 K in
                      agreement with the unusual temperature dependence of the
                      magneto-crystalline anisotropy. A sum rule analysis of the
                      XMCD spectra revealed that the transitions observed with
                      XMCD are due to changing effective Fe spin moments. Since
                      the transitions were not observed with VSM, we attribute
                      them to changes of the intra-atomic dipole moment of the Fe
                      3d spin-density distribution, i.e. the Tz term in the XMCD
                      sum rule for the effective spin moment. This conclusion was
                      verified and explained theoretically. The sizable negative
                      intra-atomic dipole moment in the monoclinic low-temperature
                      phase of magnetite is due to the contribution of Fe2+ ions
                      on B4 sites (-1.44 μB per atom) which is partly compensated
                      by Fe2+ ions on B1 sites (0.72 μB per atom). It is a local
                      indicator for the Verwey transition in small magnetite
                      nanoparticles which is usually screened by blocking effects
                      in classical magnetometry.},
      month         = {Aug},
      date          = {2015-08-30},
      organization  = {XAFS16 satellite meeting
                       “Application of XAFS to the study of
                       magnetic Materials”, Stuttgart
                       (Germany), 30 Aug 2015 - 2 Sep 2015},
      cin          = {PGI-6},
      cid          = {I:(DE-Juel1)PGI-6-20110106},
      pnm          = {522 - Controlling Spin-Based Phenomena (POF3-522)},
      pid          = {G:(DE-HGF)POF3-522},
      typ          = {PUB:(DE-HGF)24},
      url          = {https://juser.fz-juelich.de/record/281650},
}