相关实验视频
Updated: May 12, 2026
08:25
Chemical Vapor Deposition of an Organic Magnet, Vanadium Tetracyanoethylene
Published on: July 3, 2015
高温金属有机磁铁高温金属有机磁铁
Rajsapan Jain1, Khayrul Kabir, Joe B Gilroy
1Department of Chemistry, University of Victoria, PO Box 3065 STN CSC, Victoria, British Columbia V8W 3V6, Canada.
Nature
|January 19, 2007
概括
研究人员使用基于溶液的化学方法开发了新的金属有机材料,在室温以上实现了磁性秩序. 这些稳定的磁铁提供可调节的特性,桥梁无机和基于分子的材料.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 物理 物理学 物理
背景情况:
- 开发分子磁铁作为传统磁铁的替代品是具有挑战性的,因为罕见的室温排序和可重现性问题.
- 传统的磁铁依赖于高温金路线,限制了性能调节和制造方法.
研究的目的:
- 为新型金属有机材料提供基于溶液的多功能合成,其磁顺序高于室温.
- 探索这些新材料的磁性和结构特征.
主要方法:
- 使用 bis(1,5-cyclooctadiene) 和三个有机受体之间的基于溶液的反应:四乙烯 (TCNE),7,7,8,8-四二二甲 (TCNQ) 和2,3-二-5,6-二-1,4-二 (DDQ).
- 通过使用磁性测量来确定订序温度和歇斯底里斯,对由此产生的金属有机材料进行了表征.
- 分析了合成化合物的固体测量和成分.
主要成果:
- 合成了三种新的金属有机化合物,具有独特的 2:1 Ni:A 固态度,与传统的 MA 类型磁铁不同.
- 在所有三种化合物中,在室温下观察到自发的取决于场的磁化和歇斯底里.
- 确定磁性排序温度明显高于环境温度,表明强大的磁性行为.
结论:
- 新型金属有机材料表现出稳定的磁性秩序远高于室温,通过多功能基于溶液的途径实现.
- 这些化合物代表了在无机和基于分子的材料的界面上的新类磁铁,为可调节的磁性提供了潜在的磁性.
- 这些发现挑战了室温分子磁铁的稀有性,并为未来的材料开发提供了有希望的途径.
更多相关视频
相关概念视频
03:02Colors and Magnetism
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 eye.
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 eye.
01:23Properties of Organometallic Compounds
Organometallic compounds are compounds that contain a carbon–metal bond. Carbon belongs to an organyl group like alkyl, aryl, allyl, or benzyl groups. The metal can be from Group I or Group II of the periodic table, a transition metal, or a semimetal.
01:25Eddy Currents
Since eddy currents occur only in conductors, magnets can separate metals from other materials. For example, in a recycling center, trash is dumped in batches down a ramp, beneath which lies a powerful magnet. Conductors in the trash are slowed by eddy currents, while nonmetals in the trash move on, separating from the metals. This works for all metals, not just ferromagnetic ones.
Other major applications of eddy currents appear in metal detectors and the braking systems of trains and roller...
Other major applications of eddy currents appear in metal detectors and the braking systems of trains and roller...
01:28Types Of Superconductors
A superconductor is a substance that offers zero resistance to the electric current when it drops below a critical temperature. Zero resistance is not the only interesting phenomenon as materials reach their transition temperatures. A second effect is the exclusion of magnetic fields. This is known as the Meissner effect. A light, permanent magnet placed over a superconducting sample will levitate in a stable position above the superconductor. High-speed trains that levitate on strong...
01:31Ferromagnetism
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...
01:18Other Unique Bacteria
Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic and are commonly found near the...