Estimating and modeling charge transfer from the SAPT induction energy

Area of Science:

• Computational chemistry
• Molecular modeling
• Quantum mechanics

Background:

• Recent quantum mechanics studies highlight the significance of charge transfer energy in short-range intermolecular interactions.
• Current polarizable and non-polarizable force fields often neglect this crucial charge transfer component.
• Existing methods for analyzing charge transfer can suffer from divergence issues.

Purpose of the Study:

• To develop an empirical method for decomposing SAPT induction energy into charge transfer and polarization components.
• To address the divergence issue in charge transfer energy calculations.
• To integrate a charge transfer model into the AMOEBA polarizable force field.

Main Methods:

• Empirical decomposition of SAPT induction energy (ED-SAPT).
• Mimicking regularized SAPT methods for divergence-free calculations.
• Extension of the charge transfer concept within the AMOEBA force field framework.

Main Results:

• The proposed ED-SAPT method provides a reliable reference for force field development by avoiding divergence.
• A consistent approach for treating charge transfer phenomena in the AMOEBA force field was established.
• Initial results demonstrate the potential of the new charge transfer model.

Conclusions:

• The developed empirical decomposition method offers a robust way to quantify charge transfer energy.
• Incorporating charge transfer into polarizable force fields like AMOEBA is feasible and promising.
• This work paves the way for more accurate molecular simulations and force fields.