Investigations on the Topographic and Spectroscopic Imaging by the Scanning Tunneling Microscope
We present theoretical and experimental results on the imaging capabilities of the scanning tunneling microscope (STM). First, we report on the metrological application of the STM to defined probing of surface profiles on a nanometer scale. For a well-defined tip shape, a systematical quantitative analysis can be made to obtain quite accurate measurements, at least in some cases. The second example we consider is organic molecules imaged with submolecular resolution at ambient conditions. Pictures obtained experimentally are interpreted by Hartree-Fock calculations for (oxy-)cyano-biphenyl-alkanes and for metal-phthalocyanines. Moreover, new spectroscopic results — only accessible under ultrahigh vacuum (UHV) — are predicted theoretically.
KeywordsScanning Tunneling Microscope Highly Orient Pyrolytic Graphite Total Electron Density Scanning Tunneling Spectroscopy Sample Electrode
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