Table 3. “MAD TS Small” refers to the MAD from B3LYP in barrier heights computed using the small structural models listed in Table 2 and similarly for the reaction energies (“MAD RxnE Small”).

The values labeled “Big” are the corresponding MADs computed for the large systems taken from Table 1. The columns marked Δ are the MADs for the changes in barrier heights and reaction energies listed in Table 2. All values are in kcal/mol.

	MAD TS Small	MAD TS Big	MAD RxnE Small	MAD Rxn Big	ΔBarrier	ΔRxnE
PM6	8.0	5.2	6.1	4.0	2.4	2.5
PM7	7.7	7.0	5.8	7.2	3.0	3.1
PM7-TS	21.7	14.3			5.9
DFTB3	5.6	6.5	5.5	6.8	2.3	2.4