The MC-DFT approach to the M06-2X, B2K-PLYP, and B2T-PLYP functionals

We have tested the performance of three recently developed density functionals, including M06-2X, B2K-PLYP, and B2T-PLYP, on thermochemical kinetics using the multi-coefficient density functional theory (MC-DFT). The results indicated that in most cases, the accuracy can be significantly improved by using more than one basis set. Compared with using a single large basis set, the atomization energies can be predicted more accurately at a lesser or equal cost, and the same level of accuracy can be reached using less expensive basis set combinations. The three combinations pdz/MG3S, pdz/ptz/apdz, and pc1/pc2/apc1 are especially attractive in this regard.