一个双核复合体,具有前所未有的阳极和阴极氧化还原开关,用于单分子磁活性
Skye Fortier1, Jennifer J Le Roy, Chun-Hsing Chen
1Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|September 3, 2013
概括
这项研究介绍了一种复合体,表现出单分子磁铁行为. 它的氧化和减少形式显示可逆磁切换,提供双开/关控制.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 磁电化学 磁电化学 磁电化学
背景情况:
- 偏磁双核 ((II) 复合物对磁性应用有兴趣.
- 单分子磁铁 (SMM) 需要特定的结构和电子特性来实现其功能.
研究的目的:
- 研究一种新型双核 (II) 复合物的氧化还原行为和磁性特性.
- 探索这个复合体作为可切换的单分子磁铁的潜力.
主要方法:
- 二核 ((II) 复合体dmp2Nin{Co[N(SiMe3) 2}的合成和表征2.
- 使用化学和电化学方法进行单电子氧化和还原.
- 结构分析 (X射线衍射) 和磁敏度测量.
- 电子偏磁共振 (EPR) 光谱学.电子偏磁共振 (EPR) 光谱学.
主要成果:
- 实现了复合物的可逆单电子氧化和还原,形成了基盐 [1(OEt2) ](+) 和 [1](-).
- 氧化还原活性局部化在nindigo配体上,产生以配体为中心的基因.
- 这些基因在 (II) 中心之间调节磁性合,诱导SMM行为.
- 氧化和还原形式都表现出SMM特性.
结论:
- 双核复合体在氧化还原操纵后显示了联结体中心的基质形成.
- 该系统展示了第一个具有可逆双"开/关"切换能力的单分子磁铁的例子.
- 这些发现为设计可切换的分子磁性材料打开了道路.
相关概念视频
Colors 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.
Valence Bond Theory
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...
Redox Reactions
Oxidation-reduction or redox reactions involve the transfer of electrons from one molecule or atom to another. When an atom gains an electron, another atom must lose an electron, meaning oxidation and reduction must occur together. Since the redox occurs in pairs, the atom that gets oxidized is also called the reducing agent or reductant, and the atom that is reduced is also called the oxidizing agent or oxidant. A straightforward way to remember the definitions of oxidation and reduction is...
Redox Reactions
Redox reactions are vital biochemical processes that underpin energy metabolism in cells. These reactions involve the transfer of electrons between molecules, occurring in tandem as oxidation and reduction. Oxidation refers to the loss of electrons, while reduction denotes their gain. This coupling ensures the seamless flow of electrons through metabolic pathways. For example, in bacterial metabolism, glucose undergoes oxidation to carbon dioxide, while oxygen is simultaneously reduced to...
Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Ferromagnetism
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...


