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Updated: Apr 28, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Crystal structure and magnetism of Fe2(OH)[B2O4(OH)]
Yotaro Kurayoshi1, Shigeo Hara, Hirohiko Sato
1Department of Physics, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
Abstract:
The structure and magnetism of Fe2(OH)[B2O4(OH)] are reported. Powder x-ray diffraction reveals a characteristic structure containing two crystallographically independent zigzag-ladder chains of magnetic Fe(2+) ions. Magnetization measurements reveal a phase transition at 85 K, below which a weak spontaneous magnetization (≈ 0.15 μB/Fe) appears. Below 85 K, magnetization increases with decreasing temperature down to 70 K, below which it decreases and approaches a constant value at low temperature. The Mössbauer spectrum at room temperature is composed of two paramagnetic doublets corresponding to the two crystallographic Fe(2+) sites. Below 85 K, each doublet undergoes further splitting because of the magnetic hyperfine fields. The temperature dependence of the hyperfine field is qualitatively different for the two distinguishable Fe(2+) sites. This is responsible for the anomalous temperature dependence of the magnetization.
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