チオラートで保護された金ナノクラスターのキラル逆転,Au-S結合を破ることなくコア再構築
1Departments of Physics and Chemistry, Nanoscience Center , University of Jyväskylä , FI-40014 Jyväskylä , Finland.
Journal of the American Chemical Society
|March 20, 2019
まとめ
キラルゴールドナノクラスター (AuNC) は,金属と硫黄の結合破裂だけでなく,コア回転を通じてキラル性を逆転させることができます. このコア回転メカニズムは エネルギー障壁が低く 安定したキラルナノマテリアルの理解と設計に不可欠です
科学分野:
- コンピュータ化学
- ナノ材料科学
- ステレオ化学
背景:
- キラルゴールドナノクラスター (AuNC) は,独特の光学および触媒特性を持っています.
- AuNCにおけるキラル逆転のメカニズムを理解することは,その安定性と応用に不可欠です.
- 現存するモデルは,金属と硫黄の結合破裂を含んでいるが,これは実験的観測を完全に説明できない.
研究 の 目的:
- 黄金のナノクラスターにおける新型のヒラル逆転メカニズムを調査する.
- 逆転経路のエネルギーバリアを比較する
- ドーピングとサイズのキラル安定性への影響を評価する.
主な方法:
- 密度関数理論 (DFT) による計算
- クイラルゴールドナノクラスターのモデリング (Au38 ((SR)) 24とAu144 ((SR)) 60).
- PdとAgでドーピングされたAu38(SR) 24の微生物の分析
主要な成果:
- コレクティブ・ゴールド・コア・ローテーションを含む新しいキラル・インバーション・メカニズムが提案されました.
- 金属と硫黄の結合破裂 (2.5 eV) と比較して,Au38とPdドーピングされたAu38のコア回転に対してより低いエネルギーバリア (1-1.5 eV) を計算した.
- より大きなAu144 ((SR)) 60クラスターでは,より高い反転バリア (2.5-2.8 eV) が発見され,より高い安定性を示唆した.
結論:
- AuNCのキラル反転は,コアのサイズ,構造,金属組成に敏感です.
- 提案されたコア回転メカニズムは,キラル逆転のための低エネルギー経路を提供します.
- Enantiopure Au144 ((SR) 60クラスターは,高いキラル安定性を要求するアプリケーションに希望を示しています.
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