Accurate Quantum Chemistry of Organic Molecules and Metal Complexes with Auxiliary-Field Quantum Monte Carlo
Benjamin Rudshteyn1 , James Shee 1, Guangqi Li 1, Dilek Coskun 1 , Richard A. Friesner1
1Department of Chemistry, Columbia University
We demonstrate the accuracy of GPU-enabled phaseless auxiliary-field quantum Monte Carlo (ph-AFQMC) combined with population control or a correlated sampling technique to reliably predict thermochemical properties. These properties include the ionization potentials of small organic molecules and the acidity/ionization potentials of octahedral transition metal complexes. Such predictions, as validated by comparison to experiment, will allow the development of large thermochemical databases for cases without experimental measurements for the development of more approximate methods able to simulate the properties of large enzymatic structures such as Cytochrome P450 responsible for drug metabolism in the liver and Photosystem II, responsible for solar-driven water oxidation in plants and cyanobacteria.