Theoretical Modeling of the Structure Formation in Adsorbed Overlayers Comprising Molecular Building Blocks with Different Symmetries

Controlling the geometry and functionality of multi-component self-assembled superstructures on surfaces is a complex task that requires numerous experimental tests. In this contribution, we demonstrate how computer modeling can be utilized to preselect functional tectons capable of forming low-dimensional architectures with tailored features. To this end, coarse-grained Monte Carlo simulations were conducted for a mixture of tripod and tetrapod units, each equipped with discrete centers for short-range directional interactions, and adsorbed onto a (111) crystalline substrate. The calculations conducted for various isomers of the tetrapod molecule revealed qualitatively distinct self-assembly scenarios, including mixing and segregation, depending on the directionality of interactions assigned to this tecton. The resulting superstructures were classified, and their formation was monitored using temperature-dependent metrics, such as coordination functions. The findings of this study contribute to a better understanding of the on-surface self-assembly of molecules with differing symmetries and can aid in the design of bicomponent overlayers for specific applications.