Regensburg 2019 – wissenschaftliches Programm
O 12.2: Vortrag
Montag, 1. April 2019, 15:30–15:45, H15
The electrostatic potential of atomic chains and clusters imaged quantitatively with scanning quantum dot microscopy — Philipp Leinen1,2, •Rustem Bolat1,2, Ruslan Temirov1,2, F. Stefan Tautz1,2, and Christian Wagner1,2 — 1Peter Grünberg Institut (PGI-3), Jülich, Germany. — 2JARA-Fundamentals of Future Information Technology
Fabrication of artificial atomic clusters and chains facilitates the observation and investigation of various quantum effects. The size and geometry of such assemblies influence electrostatic potentials, catalytic efficiency as well as a magnetic response. Here, we investigate the electrostatic properties of differently sized and shaped Ag clusters which have been created on a Ag(111) substrate by atomic manipulation with a scanning probe microscope (SPM). We use scanning quantum dot microscopy (SQDM) [1,2] with a single molecule quantum dot attached to the SPM tip  to image the surface potential over atomic chains and compact clusters. These potentials originate from the Smoluchowski effect and influence, e.g., the local reactivity. We find that the surface dipole moment per adatom drops rapidly for compact assemblies while it converges to a value of about 0.26 Debye for atoms in a chain.
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