アンモニアアルカリフルレリド (ND(3)) ((x) NaA(2) C(60):アンモニア特異的な効果と超伝導性
Serena Margadonna1, Efstathios Aslanis, Kosmas Prassides
1Department of Chemistry, University of Cambridge, UK.
Journal of the American Chemical Society
|August 22, 2002
まとめ
デュテラートアンモニア (ND(3) を含むフラーリドナトリウムの結晶構造を決定した. 弱いN-D...π水素結合は包装に影響を与え,ユニークな超伝導特性を説明する可能性がある.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- 化学 化学は化学です.
背景:
- 超伝導フルレリドは,ユニークな電子特性を有する材料のクラスです.
- 結晶構造を理解することは,超伝導性のメカニズムの解明に不可欠です.
- 以前の研究では,様々なフラーリド組成物とその構造を調べた.
研究 の 目的:
- 超伝導性ナトリウムフルレリドとデュテラートアンモニアの詳細な結晶構造を決定する.
- フラーライドの格子内のNa(+) -ND(3) ペアの配置と結合を調査する.
- 構造特性を観測された超伝導特性と相関させるため.
主な方法:
- シンクロトロンX線粉の difraktion. シンクロトロンX線粉の difraktion. シンクロトロンX線粉の difraktion. シンクロトロンX線粉の difraktion.
- 中性子粉の difraktion. 中性子粉の difraktion. 中性子粉の difraktion. 中性子粉の difraktion. 中性子粉の difraktion. 中性子粉の difraktion. 中性子粉の difraktion.
- クリスタル構造と原子の位置の分析.
主要な成果:
- 超伝導フルレリド (ND(3)) ((x) NaA(2) C(60) (A=K,Rb) は,低温では面中心の立方体構造を示している.
- Na(+) -ND(3) のペアは八面体間隙を占有し,相互に浸透する2つの立方体の場所の乱れを示しています.
- 弱いN-D...π水素結合相互作用は,ND(3) とC(60) 単位の間に特定されました.
結論:
- 結晶構造の特徴は,オクタエドール状の部位に無秩序なNa(+) -ND(3) のペアがあることです.
- 分子間結合は弱いN-D...π水素結合によって制御される.
- これらの水素結合は,これらのフルレリドの異常な超伝導的行動に役割を果たす可能性があります.
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