Met-enkephalin, one of the smallest opiate peptides and an important neuro-transmitter, is a widely used benchmarking problem in the field of molecular simulation. Through its range of possible low-temperature conformations separated by free-energy barriers it was previously found to be hard to thermalize using straight canonical molecular dynamics simulations. Here, we demonstrate how one can use the recently proposed population annealing molecular dynamics scheme to overcome these difficulties. We show how the use of multi-histogram reweighting allows one to accurately estimate the density of states of the system and hence derive estimates such as the potential energy as quasi continuous functions of temperature. We further investigate the free-energy surface as a function of end-to-end distance and radius-of-gyration and observe two distinct basins of attraction.
|Number of pages
|Journal of Physics: Conference Series
|Published - 1 Mar 2022
|33rd Annual CSP Workshop: Recent Developments in Computer Simulation Studies in Condensed Matter Physics - Virtual
Duration: 17 Feb 2021 → 21 Mar 2021