First-principles study of square chalcogen bond interactions and its adsorption behavior on silver surface

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Computational Chemistry

Background:

• Square chalcogen bonds (2Ch⋯2N) are increasingly recognized in crystal structures.
• Understanding these interactions is crucial for designing novel materials.
• Benzothiadiazole, benzoselenadiazole, and benzotelluradiazole dimers are key model systems.

Purpose of the Study:

• To investigate the nature and strength of 2Ch⋯2N square chalcogen bonds in benzothiadiazole derivatives.
• To explore the adsorption behavior of these dimers on Ag(110) surfaces.
• To assess the impact of fluorine substitution on chalcogen bond strength and adsorption.

Main Methods:

• Crystal Structure Database (CSD) mining to identify existing square chalcogen structures.
• First-principles calculations to model square chalcogen bonds and adsorption on Ag(110).
• Comparative analysis of non-substituted and partially fluoro-substituted complexes.

Main Results:

• The strength of the 2Ch⋯2N square chalcogen bond follows the order S < Se < Te in C6N2H4Ch dimers.
• Fluorine atom replacement in C6N2H3FCh complexes significantly enhances the 2Ch⋯2N bond strength.
• Van der Waals interactions govern the self-assembly of these dimer complexes on silver surfaces.

Conclusions:

• The study provides a systematic understanding of 2Ch⋯2N square chalcogen bond characteristics.
• Theoretical insights guide the rational design of supramolecular assemblies and advanced materials.
• The findings highlight the potential of these bonds in materials science applications.