Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK.
Small. 2013 Nov 25;9(22):3812-22. doi: 10.1002/smll.201300310. Epub 2013 Apr 30.
A combined experimental and theoretical investigation is carried out into the electrical transport across a fullerene dumbbell one-molecule junction. The newly designed molecule comprises two C60 s connected to a fluorene backbone via cyclopropyl groups. It is wired between gold electrodes under ambient conditions by pressing the tip of a scanning tunnelling microscope (STM) onto one of the C60 groups. The STM allows us to identify a single molecule before the junction is formed through imaging, which means unambiguously that only one molecule is wired. Once lifted, the same molecule could be wired many times as it was strongly fixed to the tip, and a high conductance state close to 10(-2) G0 is found. The results also suggest that the relative conductance fluctuations are low as a result of the low mobility of the molecule. Theoretical analysis indicates that the molecule is connected directly to one electrode through the central fluorene, and that to bind it to the gold fully it has to be pushed through a layer of adsorbates naturally present in the experiment.
对富勒烯哑铃型单分子结的电输运进行了实验和理论的综合研究。新设计的分子由两个 C60 通过环丙基连接到芴的骨架上。在环境条件下，通过将扫描隧道显微镜（STM）的尖端压在一个 C60 上，将其连接到金电极之间。STM 允许我们在形成结之前通过成像来识别单个分子，这意味着明确地只有一个分子被连接。一旦提起，同一个分子可以被连接多次，因为它被强烈地固定在尖端上，并且发现了一个接近 10(-2) G0 的高电导状态。结果还表明，由于分子的低迁移率，相对电导波动较低。理论分析表明，分子通过中心芴直接连接到一个电极，并且为了将其完全连接到金电极，它必须通过实验中自然存在的吸附层被推动。
