The chlorobenzene-argon ground state intermolecular potential energy surface

Area of Science:

• Computational Chemistry
• Physical Chemistry
• Molecular Interactions

Background:

• Van der Waals complexes are crucial for understanding intermolecular forces.
• Chlorobenzene-argon interactions are not fully characterized.
• Accurate potential energy surfaces are needed for spectroscopic analysis.

Purpose of the Study:

• To compute the ground state intermolecular potential energy surface (PES) of the chlorobenzene-argon complex.
• To determine the equilibrium geometry and well depth of the complex.
• To calculate vibrational states for comparison with experimental data.

Main Methods:

• Coupled cluster singles and doubles with connected triple excitations (CCSD(T)) model.
• Augmented correlation consistent polarized valence double zeta (aug-cc-pVDZ) basis set.
• Inclusion of midbond functions for accurate description of the van der Waals interaction.

Main Results:

• The global minimum of the PES was found at a well depth of 420 cm⁻¹.
• The equilibrium geometry features an argon atom at 3.583 Å from the chlorobenzene plane, with a specific angular orientation.
• Calculated vibrational eigenvalues were used to refine experimental assignments.

Conclusions:

• The computed PES accurately describes the chlorobenzene-argon interaction.
• The study provides a benchmark for theoretical calculations on similar systems.
• The results aid in the interpretation of experimental spectroscopic data.