チオラートで保護されたAu(20) クラスタは,2.1 eVの大きなエネルギーギャップを持つ
Manzhou Zhu1, Huifeng Qian, Rongchao Jin
1Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA.
Journal of the American Chemical Society
|May 13, 2009
まとめ
合成された新金クラスター,Au ((20) (((SCH ((2) CH ((2) Ph)) ((16)) は,量子閉じ込めと強化された安定性を表しています. これらの20原子の黄金のクラスターは,以前に研究されたクラスターよりも大きな光学エネルギーギャップを持っています.
科学分野:
- ナノテクノロジー ナノテクノロジー
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
背景:
- チオラートで覆われた黄金のクラスターは,そのユニークな電子的および光学的性質のために興味があります.
- 特定の黄金クラスターサイズの合成と安定性を理解することは,その適用に不可欠です.
研究 の 目的:
- 20原子の黄金クラスターの動力的に制御された合成を開発する.
- 合成されたクラスターの組成,光学特性,および安定性を特徴付ける.
- Au(20)(SCH(2)CH(2)Ph)(16) の性質を他の黄金のクラスターと比較する.
主な方法:
- 運動制御された合成.
- 電子スプレーイオン化質量スペクトロメトリ (ESI MS).
- 基本分析,X線光電子スペクトロスコピー (XPS),核磁共振 (NMR),熱重力測定分析 (TGA) などを行っています.
- 光学吸収スペクトロスコーピー. 光学吸収スペクトロスコーピー.
主要な成果:
- 組成のAu(20)(SCH(2)CH(2)Ph)(16).のチオラートで覆われた20原子の黄金のクラスタを成功して合成しました.
- 段階的な光学吸収スペクトルと,約2.15 eVの光学エネルギーギャップを持つ観測された量子閉じ込め行動.
- 過剰なチオールエッチングに対して例外的な強度を示し,より小さな金塊と対照的です.
結論:
- 合成されたAu) 20 (SCH) 2 (CH) 2 (Ph) 16のクラスターは,ユニークな光学特性と安定性を発揮します.
- 観測された性質は,他の黄金クラスターと比較して,潜在的な構造的な違いを示唆しています.
- Au ((20) ((SCH ((2) CH ((2) Ph)) ((16) の結晶構造に関するさらなる調査が必要である.
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