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.

A lattice model of terephthalic acid (TPA) and iron ordering on the Cu(100) surface is proposed and investigated using Monte Carlo simulation in a grand canonical ensemble. We have an evidence that the emergence of all the experimentally observed metal−organic structures cannot be explained in terms of short-ranged interactions such as hydrogen bonding and metal−carboxylate coordination proposed and discussed in earlier papers. The self-assembly of the "cloverleaf" and "interlocked" structures requires the presence of long-ranged TPA−Fe interaction. The unidentate carboxylate−Fe interaction is demonstrated to be 0.6−0.7 times weaker as compared to the bidentate bond. The phase diagram with all the experimentally observed structures is obtained. It has been established that one type of the ladder structures distinguished on scanning tunneling microscopy images is a metastable state and not a phase in the thermodynamic sense. We have found two new metal−organic structures, which are missed in earlier studies, but apparently formed in the TPA−Fe/Cu(100) adsorption layer. The first one comprises the single −Fe−TPA− rows linked with the TPA molecules in dihapto hydrogen bond motif. This phase is characterized by the lowest density of the monolayer. Another phase is formed at high densities and composed of the alternating rows of "cloverleaves" and TPA molecules linked with a pair of Fe atoms.

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A simple lattice model of metal-organic adsorption layers self-assembling on the Au(111) surface and based on pyridyl-substituted porphyrins differing by the number of functional groups and their position has been...

We present to the scientific community the Surface Science Modeling and Simulation Toolkit (SuSMoST), which includes a number of utilities and implementations of statistical physics algorithms and models. With SuSMoST it is possible to predict or explain the structure and thermodynamic properties of adsorption layers. SuSMoST automatically builds formal graph and tensor-network models based on atomic description of adsorption complexes and helps to do ab initio calculations of interactions between adsorbed species. Using methods of various nature SuSMoST generates representative samples of adsorption layers and computes its thermodynamic quantities such as mean energy, coverage, density, and heat capacity. From these data one can plot phase diagrams of adsorption systems, assess thermal stability of self-assembled structures, simulate thermal desorption spectra, and so forth.