Supramolecular nanotubes based on halogen bonding interactions: cooperativity and interaction with small guests

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Computational Chemistry

Background:

• Noncovalent interactions, particularly halogen bonding, are crucial for self-assembly.
• Supramolecular nanotubes (SNTs) offer unique properties for molecular recognition and encapsulation.
• Designing ordered supramolecular structures requires understanding the principles of noncovalent interactions.

Purpose of the Study:

• To investigate the formation of supramolecular nanotubes (SNTs) driven by halogen bonding.
• To explore the influence of halogen atom orientation on SNT formation.
• To assess the ion encapsulation capabilities of the designed SNTs.

Main Methods:

• Computational modeling using BP86-D3/def2-TZVP and RI-MP2/def2-TZVP levels of theory.
• Analysis of formation energies for binary and ternary assemblies.
• Systematic study of SNTs constructed from benzene and pyridine/benzonitrile rings with varying halogen substituents (Br, I).

Main Results:

• Successfully modeled the formation of SNTs governed by halogen bonding interactions.
• Determined the impact of halogen atom orientation (parallel vs. antiparallel) on assembly stability.
• Demonstrated the ability of these SNTs to encapsulate both anions and cations within their structure.

Conclusions:

• Halogen bonding, specifically the σ-hole interaction, is a powerful tool for designing and constructing supramolecular nanotubes.
• The studied SNTs show promise for applications requiring selective ion binding and controlled self-assembly.
• This work provides a computational approach for generating novel supramolecular architectures.