Effective Fragment Potential Method: Past, Present, and Future

This chapter focuses on the use of the effective fragment potential (EFP) method as a polarizable embedding scheme for describing electronic excitation, ionization, and attachment processes in condensed phase, interfaces, and biological systems. It suggests ways of extending the EFP method to flexible molecules. EFP can be combined with quantum-mechanical (QM) methods in a QM/molecular mechanics (MM) fashion, providing polarizable embedding for the description of chemical and photochemical phenomena in condensed phases. The chapter provides detailed description of two exemplary cases of QM/EFP usage. It also shows that the QM/macro-EFP (mEFP) approach provides a rigorous way to incorporate polarization embedding into studies of biological systems. The presented authors' work is focused along some of the following directions: development of an EFP-based force field for polymers and macromolecules; development of computationally efficient schemes that allow flexibility in fragments' geometries; and development of fully-coupled QM-EFP schemes capable of exploring dynamics of electronically excited species in various environment.