Charge transfer and cation order degrees of freedom and magnetism have been investigated in hexagonal, 9R-type, BaRu1-xMnxO3 solid solutions for 0<x<0.9. The cell parameters and volume follow a "charge transfer Vegard's law," with two linear regions that meet at x=0.5 evidencing a significant Mn4+ + Ru4+ -> Mn3+ + Ru5+ charge transfer. Cation order anomalies at x = 1/3 and 2/3 evidence some Mn/Ru clustering within trimer units. The two charge regimes give rise to distinctive magnetic behaviors. Spin freezing near 25 K is observed for samples with x < 0.4, but above x=0.5 a Neel transition increases from 125 to 270 K at x=0.9. Neutron diffraction reveals an antiferromagnetic structure with a (001/2) propagation vector and two-dimensional critical behavior for the x=0.8 material.
|Number of pages||8|
|Journal||Physical review B: Condensed matter and materials physics|
|Publication status||Published - Sep 2009|
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