金属表面に横たわるアルキルチオラートの自己組み立てモノレイヤーの相応の固体-固体相変遷
Y Wang1, J G Solano-Canchaya, M Alcamí
1Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain. yang.wang@uam.es
Journal of the American Chemical Society
|July 26, 2012
まとめ
Pt{111}上のアルキルチオラートによる自己組み立てモノレイヤー (SAM) は,温度によって誘発された固体-固体相移行を示します. 冷却によってアルキルチオラート鎖が傾き,連鎖の相互作用によって引き起こされ,デバイスの設計に影響を与えます.
科学分野:
- 表面科学とは,地表科学である.
- マテリアルサイエンス 材料科学
- コンピューティング・ケミストリー
背景:
- 自己組み立てモノレイヤー (SAM) は,表面科学とナノテクノロジーにおいて極めて重要です.
- SAMのフェーズトランジションを理解することは,物質特性制御の鍵です.
- 金属の表面上のアルキルチオラートは,潜在的な応用を持つ秩序付けられた構造を形成します.
研究 の 目的:
- Pt ((111) 上のアルキルチオラートSAMの温度誘発相変遷を調査する.
- アルキル鎖の方向変化を制御するメカニズムを解明する.
- 関連系における類似の相変異の条件を特定する.
主な方法:
- 分子動力学シミュレーションが採用されました.
- Ab initio 潜在エネルギー表面は,正確な力場のために利用されました.
- シミュレーションは,Pt上での異なる鎖長を持つアルキルチオラート (SAM) に焦点を当てました.
主要な成果:
- 温度によって誘発される相応の固体-固体相変遷は, >12個の炭素原子を持つSAMについて予測されました.
- 冷却により,鎖の構成が直立から傾斜に急激に変化した.
- 移行は,ヘッドグループ相互作用ではなく,連鎖間のヴァン・デル・ワールズ相互作用によって支配されました.
結論:
- Pt(111) 上のアルキルチオラートSAMは,温度に依存する異なった相行動を示す.
- この発見は,温度制御された電子機器や光学機器の可能性を示唆している.
- 特定の格子間隔 (4.7-4.9 Å) は,Au/Agの密集した包装を除いて,これらの相移行に有利です.
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