ピリジン結合単分子結合の導電性と幾何学

M Kamenetska¹, Su Ying Quek, A C Whalley

¹Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA.

Journal of the American Chemical Society

|April 29, 2010

まとめ

ピリジン末端の分子は,黄金結合で2つの異なる導電性状態を示します. 低伝導状態は,伸縮された分子に対応し,高伝導状態は,電子輸送に影響を与える角度結合を示します.

科学分野:

分子電子 (モレキュラー・エレクトロニクス)
ナノテクノロジーナノテクノロジー
物理化学物理化学

背景:

分子-電極のインターフェイスを理解することは,分子電子工学にとって極めて重要です.
ピリジンの窒素原子は,金属電極との結合のユニークな可能性を提供します.
単一分子結合における伝導性の状態の特徴づけは,活発な研究分野である.

研究の目的:

ピリジン末端の分子の電気伝導性を測定および分析する.
分子幾何学と導電性の関係を調査する.
ピリジン・ゴールドコンタクトの結合メカニズムを解明する.

主な方法:

使用した金色の点接触が形成され,分子溶液に圧縮されます.
金分子-金結合の延長と圧縮によって測定された導電性.
理論的検証のための第一原理の伝導性計算を行いました.

主要な成果:

4つのピリジン末端の分子すべてにおいて,二元導電性シグネチャーを観測した.
分子が伸縮した低伝導状態と,角度結合した高伝導状態を識別した.
発見された交差点の伸びは,低導電状態での分子長と相関しています.

結論:

ピリジン・ゴールド結合は,2つの異なる導電性状態を可能にします.
分子の伸縮と結合角度は,交差点の伝導性に大きく影響する.
pi*軌道は,これらの結合分子における主要な伝導経路である.

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