Many-Body Dispersion.

Area of Science:

• Computational chemistry
• Quantum chemistry
• Theoretical chemistry

Background:

• Accurate calculation of many-body dispersion (MBD) is crucial for understanding intermolecular forces in large systems.
• Existing methods for MBD calculation vary in complexity, accuracy, and applicability.
• Clarifying the definition of 'body' (atom-based vs. molecule-based) is essential for consistent MBD treatment.

Purpose of the Study:

• To provide a comprehensive overview of diverse many-body dispersion calculation approaches.
• To compare and contrast different methodologies for MBD.
• To discuss the implications of atom-based versus molecule-based definitions in MBD.

Main Methods:

• Review of empirical approaches with fitted parameters.
• Discussion of augmented density functional-based methods.
• Analysis of symmetry-adapted perturbation theory (SAPT).
• Examination of supermolecule approaches using coupled cluster theory.

Main Results:

• Multiple computational strategies exist for calculating many-body dispersion.
• Empirical methods offer simplicity but may lack generalizability.
• Quantum chemical methods like coupled cluster theory provide high accuracy but are computationally expensive.
• The choice between atom-based and molecule-based definitions impacts the MBD calculation.

Conclusions:

• The selection of an appropriate MBD method depends on the desired accuracy, system size, and available computational resources.
• Further research may focus on developing more efficient and accurate MBD methods.
• Standardizing the definition of 'body' in MBD calculations is important for inter-study comparisons.