Regensburg 2019 – wissenschaftliches Programm
O 47.1: Poster
Dienstag, 2. April 2019, 18:00–20:00, Poster D
Simulation of STM images and spectroscopy of single nitrogen-doped molecules with 5-7 membered rings on Au(111) surfaces — •Seddigheh Nikipar1,3,4, Dmitry A. Ryndyk1,2, Sibylle Gemming3,4, Francesca Moresco1,4, Gianaurelio Cuniberti1,4, and Thomas Frauenheim2 — 1Institute for Materials Science, TU Dresden — 2BCCMS, Department of Physics, Universität Bremen — 3Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf — 4Center for Advancing Electronics Dresden, TU Dresden
We consider STM images and spectroscopy (STS) of molecules on metal surfaces. We combine DFT based atomistic tight-binding model (DFTB approach) with Green function technique, which offers a framework to consider tip, molecule and surface as one integrated system and taking into account the tip geometry. Besides, it captures the interference and interaction effects. This approach can be applied for the investigation of finite-voltage effects and describe the high-energy molecular transport states. It allows to simulate quantitatively the I(V) current-voltage spectroscopy curves and dI/dV maps in both constant current and constant height modes. We applied our methods to nitrogen-doped molecules with 5-7 membered rings on Au(111) surface and showed that the electronic properties of molecules are strongly influenced by formation of azulene-motifs. We developed the integrated open software suite for quantum nanoscale modeling (TraNaS OpenSuite, tranas.org/opensuite) for convenient calculations of large-scale molecular nanosystems on metal surfaces.