Au21 ((S-Adm) 15の総構造の決定とチオレートされた金ナノクラスターの幾何学/電子構造の進化
Shuang Chen1, Lin Xiong2, Shuxin Wang1
1Department of Chemistry and Center for Atomic Engineering of Advanced Materials, Anhui University , Hefei, Anhui 230601, People's Republic of China.
Journal of the American Chemical Society
|August 24, 2016
まとめ
この研究は,超小型のゴールドナノクラスターが 原子包装構造をどのように変化させるかを明らかにしています 新しい金ナノクラスター,Au21 ((S-Adm) 15) は,Au18 ((SR) 14) から成長し,六角形の密封から面中心の立方体への変換を示した.
科学分野:
- 材料科学
- ナノテクノロジー
- 化学について
背景:
- より大きな金ナノ粒子は通常,面中心の立方体 (fcc) 原子パッキングを示します.
- 超小型金ナノクラスターは,リガンド保護の影響を受けた多様な原子包装構造 (fcc,六角密閉包装 (hcp),体中心立方体 (bcc)) を示す.
- 黄金のナノクラスターにおけるこれらの包装構造間の変換メカニズムは,ほとんど未知のままです.
研究 の 目的:
- 超小型の金ナノクラスターの成長機構と構造変化を調査する.
- チオラートで保護された金ナノクラスターにおける面中心立方体 (fcc) 構造の形成の起源を解明する.
- 新しい金ナノクラスターの合成と構造的特徴を報告する,Au21 ((S-Adm)) 15.
主な方法:
- 新しいナノクラスターの全構造の決定のためのX線結晶学.
- 先駆体Au18(SR) 14ナノクラスターからAu21(S-Adm) 15を合成する.
- 成長メカニズムと電子構造を理解するための密度関数理論 (DFT) の計算.
主要な成果:
- 新しい金ナノクラスター,Au21 ((S-Adm) 15) が成功して合成され,特徴づけられました.
- 構造分析により,Au18 ((SR)) 14の六角密封 (hcp) Au9コアからAu21 ((S-Adm)) 15の面中心立方 (fcc) Au10コアへの変換が明らかになった.
- 密度関数理論 (DFT) の計算により,この構造変換を推進する幾何学的および電子的要因の洞察が得られました.
結論:
- この研究は,超小型の金ナノクラスターにおける原子包装変換の特定の例を示しています.
- この発見は,成長メカニズムと,チオラートで保護された金のナノクラスターで面中心の立方体 (fcc) 構造の形成につながる要因に関する重要な情報を提供します.
- この研究は,リガンドで保護された金ナノクラスターの構造-特性関係を理解するのに寄与する.
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