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Magnetic clusters and ferromagnetic spin glass in the novel hexagonal perovskite 12R-Ba₄SbMn₃O₁₂.

ABSTRACT: A 12-layer hexagonal perovskite Ba₄SbMn₃O₁₂ (space group: R3̄m; a = 5.72733(3) Å, and c = 28.1770(3) Å) has been synthesized by high-temperature solid-state reactions and studied using powder X-ray and neutron diffraction and magnetization measurements. This 12R polytype structure contains one corner-sharing (Sb, Mn)O₆ octahedron and a trimer of face-sharing MnO₆ octahedra per formula unit. Ba₄SbMn₃O₁₂ displays a paramagnetic state of the Mn₃ magnetic cluster at 100-200 K, which partially disassociates into individual Mn ions at 250-300 K. The ferromagnetic interaction between these Mn₃ clusters is mainly mediated by Mn³⁺ at the M1 site, leading to dynamic ferromagnetic clusters below T _D = ∼70 K and ferromagnetic spin freezing transition at T _g = ∼11.5 K. The stability of Mn₃ magnetic clusters in the 12R polytypes is related to the intracluster Mn-Mn distance.

SUBMITTER: Yan X

PROVIDER: S-EPMC10087385 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Magnetic clusters and ferromagnetic spin glass in the novel hexagonal perovskite 12R-Ba4SbMn3O12.

Yan Xiaohui X Wu Junkun J Lei Xiuyun X He Lunhua L Guo Wenbin W Kuang Xiaojun X Yin Congling C

RSC advances 20230411 17

A 12-layer hexagonal perovskite Ba4SbMn3O12 (space group: R3̄m; a = 5.72733(3) Å, and c = 28.1770(3) Å) has been synthesized by high-temperature solid-state reactions and studied using powder X-ray and neutron diffraction and magnetization measurements. This 12R polytype structure contains one corner-sharing (Sb, Mn)O6 octahedron and a trimer of face-sharing MnO6 octahedra per formula unit. Ba4SbMn ...[more]

PMID: 37057273

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