Comparison of the periodic slab approach with the finite cluster description of metal–organic interfaces at the example of PTCDA on Ag(110)

Abstract

We present a comparative study of metal-organic interface properties obtained from dispersion corrected density functional theory calculations based on two different approaches: the periodic slab-supercell technique and cluster models with 32-290 Ag atoms. Fermi smearing and fixing of cluster borders are required to make the cluster calculation feasible and realistic. The considered adsorption structure and energy of a PTCDA molecule on the Ag(110) surface is not well reproduced with clusters containing only two metallic layers. However, all clusters with four layers of silver atoms and sufficient lateral extension reproduce the adsorbate structure within 0.04 Å with respect to the slab-supercell structure and provide adsorption energies of ( -4.45± 0.08 eV) consistent with the slab result of -4.47 eV. Thus, metal-organic adsorbate systems can be realistically represented by properly defined cluster models. © 2018 Wiley Periodicals, Inc.

Computational strategies to address the catalytic activity of nanoclusters

“…34 However, the recent studies guide that cluster modeling would be a more comprehensive approach with a more robust realistic description of nanocluster features. 35,36 The notably different catalytic activity shown by Ni 85 cluster compared to the reported periodic Ni(111) surface for NO reduction to N 2 in a study from our group exemplifies this. 32 Different energetics for direct versus indirect N O bond dissociation and product selectivity were observed (Figure 1c).…”

“… 33 A customary approach in many studies of nanoclusters using slab model was rooted on the perception that higher sized nanoparticles behave similarly to the bulk owing to the diminished number of undercoordinated sites 34 . However, the recent studies guide that cluster modeling would be a more comprehensive approach with a more robust realistic description of nanocluster features 35,36 . The notably different catalytic activity shown by Ni 85 cluster compared to the reported periodic Ni(111) surface for NO reduction to N 2 in a study from our group exemplifies this 32 .…”

Trimethyloxonium ion – a zeolite confined mobile and efficient methyl carrier at low temperatures: a DFT study coupled with microkinetic analysis

“…adsorbates and predict reaction kinetics. 20,[52][53][54][55][56][57][58][59] Herein, the H-ZSM-5 framework structure was simulated by employing a large 68T cluster model (Fig. S1(a) †) that includes two characteristic channels (sinusoidal (5.1 × 5.5 Å) and straight (5.3 × 5.6 Å)) and one intersection (the diameter of the largest included sphere is 6.3 Å (ref.…”

Local Decomposition of Hybridization Functions: Chemical Insight into Correlated Molecular Adsorbates

“…It can be advantageous to truncate a surface for studying the properties of adsorbates [70][71][72][73][74][75][76], or for simulating the electron transport properties through molecules in a molecularjunction setup [77][78][79][80][81]. This is called a (truncated) cluster approach in this work.…”