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Crystal, magnetic, and electronic structures, and properties of new BaMnPnF (Pn = As, Sb, Bi).

ABSTRACT: New BaMnPnF (Pn = As, Sb, Bi) are synthesized by stoichiometric reaction of elements with BaF₂. They crystallize in the P4/nmm space group, with the ZrCuSiAs-type structure, as indicated by X-ray crystallography. Electrical resistivity results indicate that Pn = As, Sb, and Bi are semiconductors with band gaps of 0.73 eV, 0.48 eV and 0.003 eV (extrinsic value), respectively. Powder neutron diffraction reveals a G-type antiferromagnetic order below T(N) = 338(1) K for Pn = As, and below T(N) = 272(1) K for Pn = Sb. Magnetic susceptibility increases with temperature above 100 K for all the materials. Density functional calculations find semiconducting antiferromagnetic compounds with strong in-plane and weaker out-of-plane exchange coupling that may result in non-Curie Weiss behavior above TN. The ordered magnetic moments are 3.65(5) μ(B)/Mn for Pn = As, and 3.66(3) μ(B)/Mn for Pn = Sb at 4 K, as refined from neutron diffraction experiments.

SUBMITTER: Saparov B

PROVIDER: S-EPMC6504822 | biostudies-other | 2013

REPOSITORIES: biostudies-other

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Crystal, magnetic, and electronic structures, and properties of new BaMnPnF (Pn = As, Sb, Bi).

Saparov Bayrammurad B Singh David J DJ Garlea Vasile O VO Sefat Athena S AS

Scientific reports 20130101

New BaMnPnF (Pn = As, Sb, Bi) are synthesized by stoichiometric reaction of elements with BaF₂. They crystallize in the P4/nmm space group, with the ZrCuSiAs-type structure, as indicated by X-ray crystallography. Electrical resistivity results indicate that Pn = As, Sb, and Bi are semiconductors with band gaps of 0.73 eV, 0.48 eV and 0.003 eV (extrinsic value), respectively. Powder neutron diffraction reveals a G-type antiferromagnetic order below T(N) = 338(1) K for Pn = As, and below T(N) = 27 ...[more]

PMID: 23831607

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