Professor Yang Zhang
Department of Nuclear, Plasma, and Radiological Engineering
University of Illinois
Unknown Location

Monday, April 10, 2017
3:00 pm (CT)
3269 Beckman Institute

Abstract

Energy landscape, the high-dimensional hypersurface in the configuration space, has been a valuable concept in qualitatively describing non-equilibrium matter and the associated complex processes that occur over a very long timescale, such as the viscous flow of supercooled liquids, the folding of polypeptide chains into structured proteins, and the self-assembly of micro-units into functional objects. Despite extensive studies, the enduring challenge is still how to quantify the energy landscape. To address this challenge, we developed a Relaxation-Excitation Mode Analysis (REMA) framework, which incorporates the kinetic theory and the energy landscape theory by treating the many-body collisions explicitly. Using REMA, important statistics of the activation barriers (“mountains”) and metabasins (“valleys”) of the energy landscape become accessible from experimentally measurable two-point correlation functions, e.g. using quasi-elastic and inelastic scattering experiments. On the computational side, we developed an improved history-dependent metadynamics method which allows the direct sampling of the above-mentioned statistics of the potential energy landscape. In this talk, I will present our all-atom simulations of the energy landscape and the hierarchical dynamics of proteins on the timescale of seconds and the experimental verifications.