Aromatic molecules on low-index coinage metal surfaces: Many-body dispersion effects

Abstract

Understanding the binding mechanism for aromatic molecules on transition-metal surfaces in atomic scale is a major challenge in designing functional interfaces for to (opto)electronic devices. Here, we employ the state-of-the-art many-body dispersion (MBD) approach, coupled with density functional theory methods, to study the interactions of benzene with low-index coinage metal surfaces. The many-body effects contribute mostly to the (111) surface, and leastly to the (110) surface. This corresponds to the same sequence of planar atomic density of face-centered-cubic lattices, i.e., (111) > (100) > (110). The binding energy for benzene/Au(110) is even stronger than that for benzene/Ag(110), due to a larger broadening of molecular orbitals in the former case. On the other hand, our calculations show almost identical binding energies for benzene on Ag(111) and Au(111), which contradicts the classic d-band center theory that could well predict the trend in chemisorption energies for various small molecules on a number of metal surfaces. Our results provide important insight into the benchmark adsorption systems with opener surfaces, which could help in designing more complex functional interfaces.

Stability and Exchange Processes in Ionic Liquid/Porphyrin Composite Films on Metal Surfaces

“…This behavior is surprising at first sight as Ag surfaces are generally considered more reactive than Au, an expectation that is based on the classic d-band center model, which was established around small molecules on metal surfaces. 8 On the other hand, in light of the ionic nature of [C 8 C 1 Im][PF 6 ] and the larger polarizability of Au compared to Ag, 8 one could expect a larger image dipole, yielding a larger adsorption energy on Au(111). Interestingly, very similar adsorption energies were also reported for structurally simpler aromatic molecules such as benzene on Ag(111) and Au(111).…”

“…Knowledge and control of the formation and structure of self-assembled porphyrin adlayers on the surface of solid supports are essential for the synthesis of custom-tailored environments and catalysts. 5,8,9,13,14,18 The preparation of catalytically active porphyrin-functionalized metal surfaces can be achieved by physical vapor deposition (PVD) in ultrahigh vacuum (UHV). 5,9,19 One particularly popular and well-studied representative is 5,10,15,20-tetraphenylporphyrin (2H-TPP, see Figure 1a).…”

Binding energies of benzene on coinage metal surfaces: Equal stability on different metals

“…We note here that pairwise approaches to the vdW energy coupled with density functionals are unable to correctly reproduce the degeneracy of benzene adsorbed on Cu, Ag, and Au. 25,56,57…”

A topological model for predicting adsorption energies of polycyclic aromatic hydrocarbons on late-transition metal surfaces

“…We also take n ph as a variable of the model to account for the non-local interactions between metal and PAHs. These interactions include the Pauli repulsion and the van der Waals forces that were previously reported to be proportional to the number of rings in contact with the metal surface ( n ph ) 33. Therefore, the model can be written as: E bind = E ph n ph + E M–C n 1 + gE M–C n 2 where the coefficients E ph and E M–C are the energy contribution due to non-chemical bonding interactions, and to the formation of η 1 coordinations, respectively.…”