Abstract

Understanding of intermolecular interactions are essential to studies ranging from basic chemical reactions to complicated cell activities, and provide insights into catalytic mechanism and molecular/drug design. Crystallography represents the most direct experimental approach to reveal wide variety of intermolecular interactions. However, the intrinsic limitations of crystallography are the missing of dynamics attributes and low resolutions in intermolecular interactions. Computational simulations proved to the critical approach to mitigate above limitations of crystallography, thus play an important role in addressing diversity of intermolecular interactions. Hybrid quantum mechanics/molecular mechanics (QM/MM) method represents the best combination of two worlds of quantum mechanics and molecular mechanics. The core region of the system in which the targeted chemical process occurs can be considered at higher level of quantum chemistry method, while the larger remainder of the system is treated with a relatively less expensive molecular mechanics force field.

Density Function Theory (DFT) simulation is the standard tool for studying metal-containing systems. The frequently occurring π-π interactions in such systems are highly correlated and dispersion dominated, so the accuracy of DFT calculations for such interaction have been problematic. Hybrid DFT methods contain a certain portion of Hartree-Fock (HF) exact exchange, and provide reasonable treatments of dispersion forces at lower computational expenses compared to the ab intio methods. It is very meaningful to evaluate how hybrid DFT methods behave based on benchmark Moller-Plesset and Couple Cluster theory calculations in the simulation of highly-correlated molecular systems.

Speaker Bio

Dr. Yuemin Liu is a Lecturer at the Department of Chemistry at the Prairie View A&M University (PVAMU). Prior to this appointment, he has been a visiting scholar in Department of Chemistry in Rice University. He was also an instructor in the Department of Chemistry at the University of Louisiana at Lafayette from 2009 till 2016. Dr. Liu received B.S. and M.S. degrees in Analytical Chemistry from the Shanxi University and China Institute of Atomic Energy respectively and Ph.D. in Computational Chemistry from the University of Toledo. He also got his post-doctoral trainings at University of Nevada, Reno, University of Alabama at Birmingham, Loyola University Chicago.

Dr. Liu’s research interests include: 1) Quantum Mechanics/Molecular Mechanics and Molecular Dynamics simulations of protein-ligand interactions, 2) Molecular dynamics studies of protein-protein, DNA/RNA-protein and glycoprotein systems, 3) Quantum Mechanics simulations of transitions states of catalytical mechanism, and 4) Quantum Mechanics studies of SERS mechanism on nanoparticles. His current studies focus quantum mechanics studies of binding affinity between the SARS-CoV-2 virus and vaccine antibodies, and structural requirements of potential antibodies or inhibitors for COVID-19 can be addressed based on data mining and quantum mechanics calculations.