A density functional theory study of the benzene-water complex

Area of Science:

• Computational chemistry
• Physical chemistry
• Molecular interactions

Background:

• Understanding intermolecular forces is crucial in chemistry and biology.
• The benzene-water complex is a model system for studying non-covalent interactions.
• Previous studies predicted stable configurations for the benzene-water complex.

Purpose of the Study:

• To investigate the intermolecular interaction potential energy surface of the benzene-water complex.
• To identify stable and unstable configurations of the complex.
• To analyze the nature of interactions in different configurations.

Main Methods:

• Real-space pseudopotential density functional theory (DFT) was employed.
• A van der Waals density functional was utilized for accurate interaction calculations.
• The intermolecular potential energy surface was mapped.

Main Results:

• A stable configuration was observed with water above or below the benzene ring, consistent with prior research.
• An unstable saddle point configuration emerged when water was positioned at the benzene rim.
• A transition in interaction type from H(water)/π-cloud(benzene) to O(water)/H(benzene) was identified.

Conclusions:

• The study confirms stable benzene-water complex structures and reveals an unstable configuration at the rim.
• The observed structural changes are driven by shifts in intermolecular interaction mechanisms.
• Computational findings were compared with experimental and other quantum-chemical results.