Thesis Defense In Chemistry, Presented by Hung Vuong
Applications of Phaseless Auxiliary Field Quantum Monte Carlo in Transition Metal Containing Systems
Presented By: Hung Vuong
Abstract:
In this talk, I will present progress towards generating benchmark-quality data for TM-containing system with phaseless auxiliary field quantum Monte Carlo (ph-AFQMC). First, I will discuss the implementation of a new algorithm for ph-AFQMC in localized orbital basis on GPUs, which significantly reduces the scaling and memory cost of ph-AFQMC using multi-determinant trial wavefunctions. With this new machinery in our toolkit, I will then present results of three projects applying ph-AFQMC to study TM compounds. Comparison with both canonical CCSD(T) and DLPNO-CCSD(T) in finite basis set, and with experimental values at CBS limit for TM complexes of varying size and multireference characteristics is presented. These results further support the capability of ph-AFQMC to generate benchmark-level data for TM-containing systems, which presents another step towards the goal of simulating large TM clusters with complex electronic structure in metalloenzymes.