Table 4.

Single point energies (kcal/mol) for QM_opt structures (with no further relaxation) obtained using different methods.

Method/stem	AA	SA- aabb	SA- abab	SA- abab2	SA- aaab	3AA+1SS	AS	SA-aaaa
PBa	0	−24.6	−10.0	−37.2	−22.5	−0.4	+1.7	−57.8
GB	0	−16.0	−3.2	−28.3	−15.1	+5.1	+6.2	−37.7
QMb	0	+0.4	+9.8	−4.4	+3.9	+6.8	+16.7	−21.5
gas phase QM	0	+27.3	+26.1	+23.1	+30.8	+12.2	+44.6	−7.6
gas phase force field	0	+12.8	+16.6	+2.9	+17.7	+10.6	+53.6	−38.2

^aThe PB data in this Table marginally differ from the Table 1 QM→MM_opt data since additional PB relaxation has been done in the Table 1. Note that the purpose of computations in Tables 1 and 4 was slightly different. The Table 1 QM→ MM_opt calculations were done to obtain MM structures and energies using the QM_opt geometry as the start, while the purpose of Table 4 was to derive energies by all methods on entirely unprocessed QM_opt structures.

^bThe reference QM_opt data from the Table 1.