Magnetic unit cells for the perovskite. Depicted magnetic unit cells are (a) ferromagnetic unit cell for 8% Ni, (b) the ferromagnetic (unequal moment magnitudes) doubled unit cell containing B1 and B2 layers for 21% Ni, and (c) the antiferromagnetic unit cell containing B1 and B2 layers for 31% Ni. The moment directions in the basal plane and labeling of B1 and B2 layers are arbitrary and chosen for convenience.
Intensity versus scattering angle of neutron-scattering data collected at 300 K subtracted from data collected at 12 K for all Ni-substituted concentrations. Successive concentrations are offset by 200 counts.
Neutron-diffraction refinement of the La0.7Sr0.3Mn0.79Ni0.21O3 sample at 12 K (refined stoichiometric Ni content). The reflection markers below the plot are, in order, nuclear perovskite structure, ferromagnetic perovskite structure, NiO nuclear structure, and AFM NiO structure. The insets show the magnified regions around the small magnetic peaks prior to magnetic refinement.
ZFC and 100 Oe FC measurements of magnetization vs temperature for all nickel concentrations. For each sample, the ZFC is the lower while the FC is the upper segment of the curves. The vertical lines are to guide theeye.
Magnetization vs. magnetic field at 12 K for all Ni concentrations.
Crystal and ionic radii from Shannon. 26
Refined parameters: magnetic moment (μ β), a, c, volume, and χ2 versus refined Ni content from neutron-diffraction refinements. The magnetic moments are calculated on the Mn atom occupational sites and represent average magnetic moments per Mn site. The number in parenthesis represents the 1σ uncertainty in the last digit.
Calculated and refined magnetic moments (at 12 K) and charge neutrality calculation for all Ni concentrations. All columns except the last two present charge neutrality calculations, the last two columns contain calculated and refined magnetic moments using 1.54 μ β for Ni.
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