Fragment Energy Assembler (FEA)

As a follow up to the EC-MFCC method, Li and Li⁵⁸ proposed the FEA approach. This approach uses FEA Fragmentation Method combined with hydrogen caps (excatly which capping algorithm is used is not stated; we assume it is the DCLC Capping Method method like prior work from this group).

An interesting aspect of Li and Li⁵⁸ is how the energy associated with the FEA is actually computed. Since the fragments in the FEA method intersect, a normal MBE is not strictly possible. However, the FEA method uses a modified form of the usual SCF equations so that the MBE is still applicable. More specifically, the densities of the fragments, dimers, etc. are computed as normal; however, when the densities are used to compute the energy, the summations are restricted to AOs and nuclei in the pseudoatom which generated the fragment.

Name	Fragments	Embedding	Caps	Screening
FEA	FEA Fragmentation Method	N/A	DCLC Capping Method	N/A