拡張TTFディチオラートリガンドを含む単成分金複合体に基づく高伝導性結晶
Wakako Suzuki1, Emiko Fujiwara, Akiko Kobayashi
1Research Centre for Spectrochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|February 6, 2003
まとめ
新しい金複合体は,高い電気伝導性を示します. これらの材料である[Au(dmdt) ((2))) ((0+) と[Au(tmdt) ((2))) ((0+) は,金属特性により,高度な電子アプリケーションの有望性を示しています.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- 導電性材料について
背景:
- 単一コンポーネントの分子導体は,先進的な電子機器にとって極めて重要です.
- 拡張テトラチアフルバレン (TTF) ディチオラートリガンドを持つ金複合体は,新しい伝導性特性の可能性を秘めている.
研究 の 目的:
- 拡張TTFのディチオラートリガンドを用いた新しい単成分金複合体を合成し,特徴づけること.
- これらの新しい金複合体の電気伝導性と磁気特性を調査するために.
主な方法:
- 金複合体の合成 [Au (((dmdt) (((2))) (((0+)) と [Au (((tmdt) (((2))) (((0+)) である.
- 構造分析のためのシンクロトロン放射粉の difraktion.
- 圧縮された粉末の試料の電気伝導性の測定.
- 電子の振る舞いを探知するための磁気感受性測定.
主要な成果:
- 合成された金複合体[Au(dmdt) ((2)) ((0+) と[Au(tmdt) ((2)) ((0+) は,室温でそれぞれ12および15 S cm(-1) の高い電気伝導性を示した.
- 複合体1 ([Au(dmdt) ((2))) ((0+)) は,パウリのような感受性を示し,50K以上の金属的振る舞いを示した.
- 複合体2 ([Au(tmdt) ((2))) ((0+)) は,高伝導性を維持しながら100Kの磁気移行を示した.
結論:
- この研究により,高伝導性の単一成分金複合体を作製することが成功しました.
- これらの複合体は,分子エレクトロニクスでの応用の可能性のある,明確な電子および磁気特性を示します.
- コンプレックス2の導電性喪失のない磁気移行は,そのユニークな導電性特性を強調しています.
関連する概念動画
Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Network Covalent Solids
Network covalent solids contain a three-dimensional network of covalently bonded atoms as found in the crystal structures of nonmetals like diamond, graphite, silicon, and some covalent compounds, such as silicon dioxide (sand) and silicon carbide (carborundum, the abrasive on sandpaper). Many minerals have networks of covalent bonds.
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
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...
Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
EDTA: Auxiliary Complexing Reagents
EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...


