11 Molecules in Complex Environments: Solvent Models, QM/MM and QM/EFP Features, Density Embedding

11.5 Effective Fragment Potential Method

(May 16, 2021)

The Effective Fragment Potential (EFP) method is a computationally inexpensive way of modeling intermolecular interactions in non-covalently bound systems. The EFP approach can be viewed as a QM/MM scheme with no empirical parameters. Originally EFP was developed by Prof. Mark Gordon’s group, 251 Day P. N. et al.
J. Chem. Phys.
(1996), 105, pp. 1968.
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, 380 Gordon M. S. et al.
J. Phys. Chem. A
(2001), 105, pp. 293.
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and was implemented in gamess. 971 Schmidt M. W. et al.
J. Comput. Chem.
(1983), 14, pp. 1347.
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A review of the EFP theory and applications can be found in Ref. 348, 379. A related approach, also based on distributed multipoles, is called XPol; it is described in Section 12.12.

A new implementation of the EFP method based on the libefp library by Dr. Ilya Kaliman (see https://libefp.github.io) has been added to Q-Chem. 528 Kaliman I. A., Slipchenko L. V.
J. Comput. Chem.
(2013), 34, pp. 2284.
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, 529 Kaliman I. A., Slipchenko L. V.
J. Comput. Chem.
(2015), 36, pp. 129.
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The new EFP module is called EFPMAN2. EFPMAN2 can run calculations in parallel on shared memory multi-core computers and clusters of computers. EFPMAN2 is interfaced with the CCMAN and CCMAN2 modules to allow coupled cluster and EOM-CC calculations with EFP. CIS and TDDFT calculations with EFP are also available.