Dependence of dispersion coefficients on atomic environment

Area of Science:

• Computational chemistry
• Quantum chemistry

Background:

• Density-functional theory (DFT) requires corrections for accurate potential-energy curves of dispersion-bound systems.
• The exchange-hole dipole moment (XDM) model offers a non-empirical approach to calculating dispersion coefficients.

Purpose of the Study:

• To apply the XDM model to investigate the impact of atomic environment on dispersion coefficients.
• To analyze how charge, oxidation state, and hybridization affect dispersion coefficients and energy contributions.

Main Methods:

• Utilizing the exchange-hole dipole moment (XDM) model for non-empirical dispersion coefficient calculations.
• Employing density-functional theory with dispersion-energy corrections.

Main Results:

• The XDM model successfully calculates dispersion coefficients based on atomic properties.
• Significant variations in dispersion coefficients were observed due to changes in atomic charge, oxidation state, and hybridization.
• These variations directly influence the energy contributions in dispersion-bound complexes.

Conclusions:

• The XDM model is a valuable tool for understanding environmental effects on dispersion interactions.
• Accurate calculation of dispersion coefficients is crucial for precise modeling of molecular interactions in various chemical environments.