Molecular junctions consisting of a Ru(bpy)₃ oligomer between conducting carbon contacts exhibit an exponential dependence of junction current on molecular layer thickness (d) similar to that observed for other aromatic devices when d < 4 nm. However, when d > 4 nm, a change in transport mechanism occurs which coincides with light emission in the range of 600–900 nm. Unlike light emission from electrochemical cells or solid-state films containing Ru(bpy)₃, emission is bipolar, occurs in vacuum, has rapid rise time (<5 ms), and persists for >10 h. Light emission directly indicates simultaneous hole and electron injection and transport, possibly resonant due to the high electric field present (>3 MV/cm). Transport differs fundamentally from previous tunneling and hopping mechanisms and is a clear “molecular signature” relating molecular structure to electronic behavior.

中文翻译：

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对称分子连接中的稳健双极光发射和电荷传输。

由导电碳接触之间的Ru（bpy）₃低聚物组成的分子结表现出结电流对分子层厚度（d）的指数依赖性，这与在d <4 nm时观察到的其他芳香族装置相似。但是，当d > 4 nm时，传输机制发生变化，这与600-900 nm范围内的发光相吻合。与电化学电池或含Ru（bpy）_3的固态膜的光发射不同，发射是双极性的，在真空中发生，具有快速上升时间（<5 ms），并持续> 10 h。发光直接表明空穴和电子同时注入和传输，可能由于存在高电场（> 3 MV / cm）而共振。转运从根本上不同于以前的隧穿和跳跃机制，是将分子结构与电子行为联系起来的清晰“分子特征”。