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arXiv · 1211.5179

Local structural variation as source of magnetic moment reduction in BaFe2As2

Jennifer L. Niedziela·M. A. McGuire·T. Egami
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Abstract

We report time-of-flight neutron powder diffraction results on stoichiometric BaFe2As2. Pair distribution function analysis shows that the orthorhombic distortion in the a-b plane at short distances are significantly different from the average lattice distortion, indicating local variations in the lattice at the short-range. We propose that this local variation reflects a high density of nano-twins, short-ranged structures which locally affect the magnetic alignment. This results suggests that the discrepancies between the observed and calculated magnetic moments in BaFe2As2 arise partly from short-ranged variation of the lattice in the a-b plane.

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Jennifer L. Niedziela, M. A. McGuire, T. Egami. 2012-11-22. Local structural variation as source of magnetic moment reduction in BaFe2As2. https://doi.org/10.1103/physrevb.86.174113

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