Nanocrystalline PrFexMn1-xO3 (x = 0.1, 0.3, 0.5, 0.7, 0.9, and 1.0) compounds were synthesized via the auto-combustion sol–gel method to investigate the influence of Fe substitution on their structural and magnetic properties. X-ray diffraction (XRD) and Rietveld refinement confirmed that all compositions crystallize in a single-phase orthorhombic structure with a Pbnm space group, indicating successful incorporation of Fe3+ ions into the perovskite lattice without secondary phase formation. Lattice parameters exhibit slight variations with Fe doping, associated with a minor increase in unit cell volume resulting from structural distortion. The magnetization (M–H) curves, measured at 300 K and 2 K, exhibit a clear evolution in the magnetic response with increasing Fe content. Samples with low Fe concentration (x ≤ 0.3) display paramagnetic-like behavior with weak magnetization, whereas the x = 0.5 composition reveals a transition toward partial magnetic ordering driven by competing Fe3+–O–Mn3+ and Fe3+–O–Fe3+ superexchange interactions. For higher Fe concentrations (x ≥ 0.7), the compounds exhibit antiferromagnetic (AFM) characteristics, with a significant decrease in magnetization at both temperatures, confirming the stabilization of AFM coupling and the suppression of Mn-based magnetic contributions. At 295 K, the 57Fe Mössbauer spectra of PrFexMn1-xO3 show a clear compositional dependence: samples with x ≤ 0.5 exhibit a paramagnetic doublet characteristic of high-spin Fe3+, whereas the x = 0.7 composition displays a broadened magnetic sextet, analyzed using the Hesse–Rübartsch field distribution model, indicating the onset of magnetic ordering. For x ≥ 0.9, well-resolved magnetic sextets are observed, confirming the establishment of long-range Fe3+–O–Fe3+ antiferromagnetic (AFM) ordering at room temperature. Upon cooling to 78 K, the Mössbauer spectra reveal a similar compositional trend with enhanced magnetic resolution: the x ≤ 0.3 samples remain predominantly paramagnetic, while x ≥ 0.5 progressively develop magnetic sextets with increasing hyperfine magnetic field (Bhf), evidencing stronger Fe3+–O–Fe3+ superexchange interactions and the consolidation of long-range AFM order at low temperature.

Magnetostructural and Mössbauer study of Fe-doped PrMnO₃ perovskites

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发表日期：

2026年4月22日

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I. Z. Al-Yahmadi,
F. Al Ma’Mari,
A. Gismelseed,
H. Widatallah,
A. Al Saadi,
A. Al-Rawas,
M. Elzain

摘要

Nanocrystalline PrFe_xMn_1-xO₃ (x = 0.1, 0.3, 0.5, 0.7, 0.9, and 1.0) compounds were synthesized via the auto-combustion sol–gel method to investigate the influence of Fe substitution on their structural and magnetic properties. X-ray diffraction (XRD) and Rietveld refinement confirmed that all compositions crystallize in a single-phase orthorhombic structure with a Pbnm space group, indicating successful incorporation of Fe³⁺ ions into the perovskite lattice without secondary phase formation. Lattice parameters exhibit slight variations with Fe doping, associated with a minor increase in unit cell volume resulting from structural distortion. The magnetization (M–H) curves, measured at 300 K and 2 K, exhibit a clear evolution in the magnetic response with increasing Fe content. Samples with low Fe concentration (x ≤ 0.3) display paramagnetic-like behavior with weak magnetization, whereas the x = 0.5 composition reveals a transition toward partial magnetic ordering driven by competing Fe³⁺–O–Mn³⁺ and Fe³⁺–O–Fe³⁺ superexchange interactions. For higher Fe concentrations (x ≥ 0.7), the compounds exhibit antiferromagnetic (AFM) characteristics, with a significant decrease in magnetization at both temperatures, confirming the stabilization of AFM coupling and the suppression of Mn-based magnetic contributions. At 295 K, the ⁵⁷Fe Mössbauer spectra of PrFe_xMn_1-xO₃ show a clear compositional dependence: samples with x ≤ 0.5 exhibit a paramagnetic doublet characteristic of high-spin Fe³⁺, whereas the x = 0.7 composition displays a broadened magnetic sextet, analyzed using the Hesse–Rübartsch field distribution model, indicating the onset of magnetic ordering. For x ≥ 0.9, well-resolved magnetic sextets are observed, confirming the establishment of long-range Fe³⁺–O–Fe³⁺ antiferromagnetic (AFM) ordering at room temperature. Upon cooling to 78 K, the Mössbauer spectra reveal a similar compositional trend with enhanced magnetic resolution: the x ≤ 0.3 samples remain predominantly paramagnetic, while x ≥ 0.5 progressively develop magnetic sextets with increasing hyperfine magnetic field (B_hf), evidencing stronger Fe³⁺–O–Fe³⁺ superexchange interactions and the consolidation of long-range AFM order at low temperature.

Magnetostructural and Mössbauer study of Fe-doped PrMnO3 perovskites

摘要

Magnetostructural and Mössbauer study of Fe-doped PrMnO₃ perovskites