Charge-Induced Structural Changes in a Single Molecule Investigated by Atomic Force Microscopy

Philipp Scheuerer, Laerte L. Patera, Felix Simbürger, Fabian Queck, Ingmar Swart, Bruno Schuler, Leo Gross, Nikolaj Moll, Jascha Repp
2019 Physical Review Letters  
Intramolecular structural relaxations occurring upon electron transfer are crucial in determining the rate of redox reactions. Here, we demonstrate that subangstrom structural changes occurring upon singleelectron charging can be quantified by means of atomically resolved atomic force microscopy (AFM) for the case of single copper(II)phthalocyanine (CuPc) molecules deposited on an ultrathin NaCl film. Imaging the molecule in distinct charge states (neutral and anionic) reveals characteristic
more » ... ferences in the AFM contrast. In comparison to density functional theory simulations these changes in contrast can be directly related to relaxations of the molecule's geometric structure upon charging. The dominant contribution arises from a nonhomogeneous vertical relaxation of the molecule, caused by a change in the electrostatic interaction with the surface.
doi:10.1103/physrevlett.123.066001 fatcat:en7wfepxxba4bar6cxj3kuxmni