キラルな鉄磁性分子金属である
José R Galán-Mascarós1, Eugenio Coronado, Paul A Goddard
1Institute of Chemical Research of Catalonia (ICIQ), Av. Paisos Catalans 16, 43007 Tarragona, Spain. jrgalan@iciq.es
Journal of the American Chemical Society
|June 24, 2010
まとめ
研究者は,フェロマグネティズム,金属伝導性,キラリティを同時に示す新しい分子材料を作成しました. このブレークスルーは,キラルな有機根幹カチオンとバイメタリックオキシラートネットワークを組み合わせ,材料科学の新たな道を開きます.
科学分野:
- 材料科学 材料科学とは
- 固体化学 固体化学
- オーガニック・エレクトロニクス
背景:
- 複数の性質が共存する分子材料の開発は大きな課題です.
- フェロ磁性,伝導性,およびキラリティは,高度な電子およびスピントロニックアプリケーションの重要な特性です.
研究 の 目的:
- フェロマグネティズム,金属のような伝導性,およびキラリティを示す新しい分子物質を合成し,特徴づけること.
- 単一の分子システムにおけるこれらの性質の相互作用を調査する.
主な方法:
- 有機/無機合成のアプローチを使用しました.
- 組み立てられたキラル有機根幹カチオンと二金属酸化物ベースのアニオンネットワークを重ね合わせた.
- シュブニコフ・デ・ハースの振動を利用して電子構造を調査した.
主要な成果:
- フェロマグネティズム,金属のような伝導性,およびキラリティの共存を持つ分子材料を成功裏に準備しました.
- キラルな有機根幹カチオンが電気伝導性と光学活動に責任を負うことを実証した.
- シュブニコフ・デ・ハースの振動によってフェルミ表面の存在が確認され,低温で明らかな隔離的振る舞いにもかかわらず.
結論:
- 合成された物質は,フェロマグネティズム,金属のような伝導性,およびキラリティを同時に持つ最初の分子システムを表しています.
- この発見は,多機能アプリケーションのための有機/無機ハイブリッド材料の潜在能力を強調しています.
- 将来の研究は,特定の技術的な用途のためにこれらの特性を調節することを探求することができます.
関連する概念動画
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...
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...
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.
Chirality
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
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...
Molecules with Multiple Chiral Centers
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...


