In the past few decades, quantum mechanical (QM) methods in computational chemistry has been used as an essential tool to gain insights into complex biochemical processes like enzymatic catalysis. However, the simultaneous QM treatment of covalent and non-covalent interactions, necessary in the description of such large chemical and biological systems, is still a computationally challenging problem given the poor scaling of QM methods. Therefore, one important research field in modern computational chemistry is the development of QM-based methodologies that are efficient and accurate for covalent and non-covalent interactions, and can be applied to large molecular systems. In this contributed poster, I will present the development of new atom-centered potentials[1,2] (ACP) that can be used in conjunction with dispersion-corrected small basis-set Hartree-Fock (HF) approximation or popular density functional theory (DFT) methods. This ACP based approach allows for an economical means of simultaneously correcting for the absence of correlation (or deficiencies in exchange-correlation functionals), basis set incompleteness, and other shortcomings of the underlying methodologies. The long-term goal of our group is to understand the fundamentals of enzymatic catalysis using the developed ACP methods, where the molecules tend to contain hundreds of atoms and are beyond the present reach of accurate QM methods. Therefore, I will show using some practical examples how the ACP approaches can be used as a valuable general-purpose tool for routine use with large molecular systems like proteins and enzymes.

References [1] DiLabio, G. A., Atom-Centered Potentials for Noncovalent Interactions and Other Applications. In Non-Covalent Interactions in Quantum Chemistry and Physics: Theory and Applications; Otero-de-la-Roza, A.; DiLabio, G. A. (Eds.); Elsevier Inc., 2017, pp 221–240 [2] Prasad, V. K.; Otero-de-la-Roza, A.; DiLabio, G. A. J. Chem. Theory Comput. 2018, 14 (2), 726–738