高強度スピンガラス アニゾトロプ Mo2FeB2-タイプ M1.5Mn1.5B2 (M = Mo, W)
Shola E Adeniji1, Alexei A Belik2, Takao Mori2,3
1Department of Chemistry, University of California, Riverside, California 92521, United States.
Journal of the American Chemical Society
|October 27, 2025
まとめ
新しい磁気材料であるMo1.5Mn1.5B2とW1.5Mn1.5B2は,高強度と組み合わせたスピンガラスの動作を示しています. これらの発見は 独特の磁気特性を有する 多機能材料の発展に道を開きます
科学分野:
- 材料科学
- 凝縮物質物理学
- マグネティズム
背景:
- 磁気材料は,スピンガラスの性質と硬い磁石の性質の両方を持ち,先進的なアプリケーションに不可欠です.
- Mo2FeB2型の構造は,その頑丈な構造特性とアルター磁性材料としての可能性で知られています.
研究 の 目的:
- Mo2FeB2型構造の新しい磁気材料を合成し,特徴づけること.
- これらの材料のスピンガラス行動と硬磁気強制力の間の結合を調査する.
- 実験的・計算的方法を用いて,磁気相互作用とアニゾトロピーを探求する.
主な方法:
- 単相Mo1.5Mn1.5B2とW1.5Mn1.5B2を実現するための固体合成経路.
- マグネティック・トランジションとスピン・ダイナミクスを検出するための温度依存およびAC感受性測定.
- 密度関数理論 (DFT) の計算により,磁気相互作用と磁気結晶アニソトロピーを決定する.
主要な成果:
- Mo1.5Mn1.5B2は,高強度 (Hc = 302.4 kA/m) のスピンガラス行動 (Tg = 29 K) を示している.
- W1.5Mn1.5B2は,再侵入クラスタースピンガラス行動 (Tg = 43 K) と強引性 (Hc = 175.1 kA/m) との鉄磁気移行 (70 K) を表している.
- DFT計算では,競合するFM/AFM相互作用と,実験観測と相関するc軸を好む単軸MAEが明らかになる.
結論:
- Mo2FeB2型の構造は,スピンガラスと硬磁石の性質を組み合わせた材料をホストすることができます.
- Mo1.5Mn1.5B2とW1.5Mn1.5B2は,有望な多機能磁気材料を表しています.
- これらの発見は,Mo2FeB2タイプの材料の応用範囲を構造上の用途を超えて拡大します.
さらに関連する動画
09:06Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
8.5K
07:42Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
Published on: July 20, 2022
3.3K
関連する概念動画
Colors and Magnetism
13.9K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
13.9K
Valence Bond Theory
11.2K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
11.2K
Ferromagnetism
3.0K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
3.0K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
1.6K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.6K
Spin–Spin Coupling: One-Bond Coupling
1.4K
Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
1.4K
Spin–Spin Coupling Constant: Overview
1.4K
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
1.4K
