Systematic Molecular Fragmentation

SMF was introduced by Deev and Collins¹¹ as a generalization of MFCC. At its core, SMF introduces a fragmentation method, and a capping method. Initial applications focused on hydrocarbons, using a relatively wide assortment of levels of theory. Absolute energies, energy barriers, bond-lengths, bond angles, and vibrational frequencies were computed and compared to the supersystem counterparts.

In a follow-up paper Collins and Deev⁶ presented the original SMF Algorithm in more detail. New this time were the Ring Repair Variation and an approximate treatment of the non-bonded interactions between distant fragments. To test the new SMF algorithm, structures were taken from the Cambridge Structural Database. Compared to the initial study the resulting molecules were chemically more diverse. Absolute energies and isomerazation eneriges were computed and compared to the respective supersystem values. Results used the SCF and MP2 methods combined with small and medium size basis sets.