Sc2C2@C80ではなく Sc2@C82:予期せぬC2v(5)-C80のテンプレート形成と,Sc2C2内部クラスタの温度に依存する動的運動
Hiroki Kurihara1, Xing Lu, Yuko Iiduka
1Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Ibaraki, Japan.
Journal of the American Chemical Society
|February 5, 2011
まとめ
研究者らは,新しい炭化物クラスターである金属フルフルレン,Sc(2)C(2)@C(2v)(5) -C(80) を発見した. その内部にあるスカンジウム炭化物 (Sc(2) C(2)) クラスタは,フルレンケージ内で温度に依存するダイナミックな動きを示している.
科学分野:
- フラーレンの化学反応
- 超分子化学とは
- マテリアルサイエンス 材料科学
背景:
- 金属フルフルレンは,金属原子またはクラスターを封じ込んでいる炭素ケージ化合物です.
- 封装された種のダイナミクスを理解することは,それらの性質と用途にとって極めて重要です.
研究 の 目的:
- 新しい炭化水素のクラスタメタロフルレレンの特徴を示すために.
- カプセル化されたSc(2) C(2) クラスタの温度に依存するダイナミクスを調査する.
主な方法:
- 構造的決定のためのX線結晶学.
- 電子構造とダイナミクスの密度関数理論 (DFT) 計算.
- 核磁共振 (NMR) スペクトロスコーピー (13Cと45Sc) で,分子対称性とダイナミクスを探求する.
主要な成果:
- Sc ((2) C ((2) @C ((2v) ((5) -C ((80)) の識別),新しい炭化物クラスター金属フルレレンである.
- 293Kでは,Sc(2) C(2) クラスターは固定され,C(s) 分子対称性が生じます.
- 413Kでは,Sc(2) C(2) クラスタの急速な回転が起こり,2つの等価なSc原子と金属の相互作用が変化します.
結論:
- この研究では,カーバイドクラスタを収容するユニークなフルレンケージ (C(2v) ((5) -C(80) が明らかになりました.
- 温度は,封じ込められたSc(2) C(2) クラスタの動的振る舞いに大きく影響し,分子対称性と金属の相互作用に影響を与えます.
関連する概念動画
Conformations of Cyclohexane
Cyclohexane does not exist in a planar form due to the high angle and torsional strain it would experience in the planar structure. Instead, it adopts non-planar chair and boat conformations.
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal tetrahedral value,...
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal tetrahedral value,...
Chair Conformation of Cyclohexane
The chair conformation is the most stable form of cyclohexane due to the absence of angle and torsional strain. The absence of angle strain is a result of cyclohexane’s bond angle being very close to the ideal tetrahedral bond angle of 109.5° in its chair conformer. Similarly, the torsional strain is also absent owing to the perfectly staggered arrangement of bonds.
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this staggered...
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this staggered...
Thermal Sigmatropic Reactions: Overview
Sigmatropic rearrangements are a class of pericyclic reactions in which a σ bond migrates from one part of a π system to another. These are intramolecular rearrangements where the total number of σ and π bonds remain unchanged.
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in 1,5-hexadiene, referred to as...
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in 1,5-hexadiene, referred to as...
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement
The Cope rearrangement is classified as a [3,3] sigmatropic shift in 1,5-dienes, leading to a more stable, isomeric 1,5-diene. The reaction involves a concerted movement of six electrons, four from two π bonds and two from a σ bond, via an energetically favorable chair-like transition state.
Stability of Substituted Cyclohexanes
This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
Cycloaddition Reactions: MO Requirements for Thermal Activation
Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.


