Improving the accuracy and reliability of M06-2X using atom-centered potentials

Current quantum mechanical (QM) simulation methods often struggle to balance accuracy with computational efficiency: They either deliver highly accurate results at significant computational cost and therefore are only applicable to small chemical systems, or they trade off accuracy for faster runtimes. In this thesis, atom-centered potentials (ACPs) were developed to enhance the accuracy of a popular low-computational-cost quantum mechanical simulation method: the M06-2X density functional combined with the 6-31+G(d,p) basis set. The ACPs were developed to target improvements in predicted bond separation energies, barrier height, reaction energies, and non-covalent interactions for chemical systems containing ten common atoms found in organic and biochemical systems (H, B, C, N, O, F, Si, P, S, and Cl). The ACPs developed herein are shown to improve the accuracy in 80.4% of the chemical properties examined.