Halogen bonded supramolecular capsules: a challenging test case for quantum chemical methods

Area of Science:

• Supramolecular Chemistry
• Quantum Chemistry
• Computational Chemistry

Background:

• A novel supramolecular capsule featuring a four-point halogen bonding interaction was recently synthesized.
• This complex molecule, composed of approximately 400 atoms, presents a significant challenge for existing quantum chemical methods.

Purpose of the Study:

• To evaluate the accuracy of a new density functional based composite method (PBEh-3c) for predicting the structure and noncovalent interactions of complex supramolecular systems.
• To assess the performance of a standard protocol for supramolecular thermochemistry.
• To propose chemical modifications for strengthening the binding interactions within the capsule.

Main Methods:

• Utilized the PBEh-3c composite method for structural and noncovalent interaction analysis.
• Employed a standard protocol for supramolecular thermochemistry calculations.
• Investigated a recently synthesized supramolecular capsule with a four-point halogen bonding interaction.

Main Results:

• The PBEh-3c method demonstrated accuracy in investigating the challenging supramolecular system.
• The study provided predictions for potential chemical modifications aimed at enhancing binding strength.

Conclusions:

• The PBEh-3c method is a viable and accurate tool for studying complex supramolecular structures and interactions.
• The findings offer insights into optimizing halogen bonding interactions for designing stronger supramolecular capsules.