Homologous Series of Flower Phases in Metal–Organic Networks on Au(111) Surface

• Published in: Journal of physical chemistry. C 2020-05, Vol.124 (21), p.11506-11515
• Main Authors: Fadeeva, Anastasiia I, Gorbunov, Vitaly A, Solovyeva, Olga S, Stishenko, Pavel V, Myshlyavtsev, Alexander V
• Format: Article
• Language: English
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.0c02527

Supramolecular coordination self-assembly on the solid surface offers great possibilities for creating nanostructures and thin films with unique physicochemical properties. In this work, we present a simple lattice model based on competitive coordination motifs that enables predictions of the phase behavior and thermal stability of metal–organic networks consisting of 1,3,5-tris­(pyridyl)­benzene (TPyB) and transition metals on the Au(111) surface. The main parameter of the model is the ratio between the energies of the two-fold and three-fold metal–ligand coordination defined by the type of the metal center. The model reveals a homologous series of flower phases that differ in the metal/ligand composition. Existing ranges of the phases in terms of the chemical potential (or partial pressure) of the components are determined by the mentioned ratio. The closer the value of this parameter is to unity, the more diverse is the phase behavior of the metal–organic network. This ratio is always greater than unity and increases in the following series Ag ≤ Cu < Ni < Co < Fe. The results of the Monte Carlo and tensor renormalization group calculations well reproduce the published experimental data on the self-assembly of metal–organic networks based on the TPyB linker. As an example, we have calculated the phase diagram of the TPyB–Cu/Au(111) adsorption layer and have estimated thermal stability of the phases. The honeycomb, flowerlike, and triangular close-packed phases are ascertained to be stable at room temperature. The remaining nanostructures appearing on the scanning tunneling microscopy images of this layer are apparently metastable.