When Surface Dynamics Fakes Symmetry -- Oxygen on Rh(100) Revisited
Abstract
Heating a long-range ordered adsorbate phase beyond its stability temperature does not necessarily result in a disordered phase, it can also break up into heavily fluctuating ordered domains. Temporal and/or spatial averaging over these fluctuations may give the impression of both a wrong periodicity and a false local symmetry. This can happen even below liquid-nitrogen temperature, so that the true nature of the phase might remain undetected. We demonstrate this scenario at the catalytically active Rh(100) surface covered by 1/2 monolayer of oxygen, using quantitative low energy electron diffraction (LEED), variable-temperature scanning tunneling microscopy (STM) and density functional theory (DFT). Using the example of CO adsorption, we show that local symmetry can have a decisive influence on the binding energy and thus the chemical reactivity.
Keywords
Cite
@article{arxiv.2508.08474,
title = {When Surface Dynamics Fakes Symmetry -- Oxygen on Rh(100) Revisited},
author = {Lutz Hammer and Tilman Kißlinger and Margareta Wagner and Reinhard B. Neder and Michael Schmid and Ulrike Diebold and M. Alexander Schneider},
journal= {arXiv preprint arXiv:2508.08474},
year = {2025}
}