Quantifying the evolution of atomic interaction of a complex surface with a functionalized atomic force microscopy tip

0538988 - FZÚ 2021 RIV GB eng J - Journal Article
Liebig, A. - Hapala, Prokop - Weymouth, A.J. - Giessibl, F.J.
Quantifying the evolution of atomic interaction of a complex surface with a functionalized atomic force microscopy tip.
Scientific Reports. Roč. 10, č. 1 (2020), s. 1-12, č. článku 14104. ISSN 2045-2322. E-ISSN 2045-2322
Institutional support: RVO:68378271
Keywords : contact * electrostatics * crystal surface * CO * AFM
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 4.380, year: 2020
Method of publishing: Open access

Previous studies have shown conflicting results regarding the electrostatic interaction, indicating in some cases that the negative charge at the apex of the CO dominates, whereas in other cases the positive charge at the end of the metal tip dominates. To clarify this, we investigated CaF 2(111). CaF 2 is an ionic crystal and the (111) surface does not possess charge inversion symmetry. Far from the surface, the interaction is dominated by electrostatics via the negative charge at the apex. Closer to the surface, Pauli repulsion and CO bending dominate, which leads to an unexpected appearance of the complex 3-atom unit cell. We compare simulated data in which the electrostatics are modeled by point particles versus a charge density calculated by DFT. We also compare modeling Pauli repulsion via individual Lennard–Jones potentials versus a total charge density overlap. In doing so, we determine forcefield parameters useful for future investigations of biochemical processes.

Permanent Link: http://hdl.handle.net/11104/0316725