Benzene adsorbed on metals: Concerted effect of covalency and van der Waals bonding

By Wei David Liu, J. Carrasco, B. Santra, A. Michaelides, Matthias Scheffler, Alexandre Tkatchenko. 2012

239 citations recorded by the source corpus.

The adsorption of aromatic molecules on metal surfaces plays a key role in condensed matter physics and functional materials. Depending on the strength of the interaction between the molecule and the surface, the binding is typically classified as either physisorption or chemisorption. Van der Waals (vdW) interactions contribute significantly to the binding in physisorbed systems, but the role of the vdW energy in chemisorbed systems remains unclear. Here we study the interaction of benzene with the (111) surface of transition metals, ranging from weak adsorption (Ag and Au) to strong adsorption (Pt, Pd, Ir, and Rh). When vdW interactions are accurately accounted for, the barrier to adsorption predicted by standard density-functional theory (DFT) calculations essentially vanishes, producing a metastable precursor state on Pt and Ir surfaces. Notably, vdW forces contribute more to the binding of covalently bonded benzene than they do when benzene is physisorbed. Comparison to experimental data demonstrates that some of the recently developed methods for including vdW interactions in DFT allow quantitative treatment of both weakly and strongly adsorbed aromatic molecules on metal surfaces, extending the already excellent performance found for molecules in the gas phase.

Subfields: Atomic and Molecular Physics, and Optics, Electrical and Electronic Engineering, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/3b8216f650aac63adf1a14aac5ff6d472561892d

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

In Electrical and Electronic Engineering

In Materials Chemistry

Citations in the corpus

Materials perspective on Casimir and van der Waals interactions (2015, background): “A particularly remarkable finding is that vdW interactions can contribute more to the binding of strongly bound molecules on transition-metal surfaces than they do for molecules physisorbed on coinage metals (Carrasco et al., 2012; Liu et al., 2012).”
van der Waals forces in density functional theory: a review of the vdW-DF method (2014, background): “However, the excellent capabilities of vdW-DF were only recently established with a string of extensive studies combining vdW-DF1 correlation with optB88 and optB86b exchange, providing accurate results for binding separations and energies both for the weaker adsorption on coinage metals and the str”