扫描隧道显微镜功能化针尖对分子能级的选择成像

Selective analysis of molecular states by functionalized scanning tunneling microscope tips

文章提出了一种通过修饰STM针尖使其功能化,调节扫描隧道显微镜(STM)的扫描偏压范围,实现对分子能级的选择性成像的方法.二萘嵌苯分子在Ag(110)表面上自组织形成的有序单层膜主要是通过分子的π电子态成像,而被二萘嵌苯分子修饰的STM针尖的能级失配于基底上吸附的分子的能级,从而只对分子的部分能级成像.这个结果为有机界面电子输运测量提供了一种更好的能级选择方法.

Selective analysis of molecular states in scanning tunneling microscopy （STM） has so fro- been achieved in a few cases by tuning the bias range of the STM in high resolution measurements. Perylene adsorbed on Ag（110） is imaged mainly through the π - states of the molecule. By functionalizing the STM tip with a perylene molecule a mismatch is created between the energy levels of the STM tip and the molecule adsorbates, so that only metal states of the underlying silver surface are imaged. This method opens a route for better energy selectivity in electron transport measurements through organic interfaces.