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Abstract

The scanning tunneling microscope (STM) is not only used to image single atoms and molecules on a surface, but also to manipulate them in a controlled way. This work aims to summarize the pioneering and most representative examples in this active research field. After an introduction into the basics of the method, the topographic and electronic origin of the images and the resulting “chemical contrast” are discussed. In addition to imaging, molecular orbitals and the chemical nature of adsorbates can be identified by spectroscopy, even if their images are equivalent. Different types of molecular manipulation are presented, including examples for all three possible driving forces: Interatomic forces without a bias voltage, electron-induced manipulation and electric-field induced processes. The lateral manipulation of molecules, including the hopping and rolling of a molecular wheel, and vertical pulling experiments are discussed. The latter ones lead to particular configurations that allow conductance measurements of single molecules between two electrodes.