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arXiv · 0907.4094

Nature of the Magnetic Order in BaMn2As2

Yogesh Singh·M. A. Green·Q. Huang·A. Kreyssig·R. J. McQueeney·D. C. Johnston·A. I. Goldman
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Abstract

Neutron diffraction measurements have been performed on a powder sample of BaMn2As2 over the temperature T range from 10 K to 675 K. These measurements demonstrate that this compound exhibits collinear antiferromagnetic ordering below the Neel temperature T_N = 625(1) K. The ordered moment mu = 3.88(4) mu_B/Mn at T = 10 K is oriented along the c axis and the magnetic structure is G-type, with all nearest-neighbor Mn moments antiferromagnetically aligned. The value of the ordered moment indicates that the oxidation state of Mn is Mn^{2+} with a high spin S = 5/2. The T dependence of mu suggests that the magnetic transition is second-order in nature. In contrast to the closely related AFe2As2 (A = Ca, Sr, Ba, Eu) compounds, no structural distortion is observed in the magnetically ordered state of BaMn2As2.

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Yogesh Singh, M. A. Green, Q. Huang, A. Kreyssig, R. J. McQueeney, D. C. Johnston, A. I. Goldman. 2009-07-23. Nature of the Magnetic Order in BaMn2As2. https://doi.org/10.1103/physrevb.80.100403

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