Smart sampling of rare events: Water exchange around metal cations
Project of Research Lab of Nadine Schwierz
Water exchange between the coordination shells of metal cations in aqueous solutions is fundamental in understanding their role in biochemical processes. Despite the importance, the microscopic mechanism of water exchange in the first hydration shell of Mg2+ has not been resolved since the exchange dynamics is out of reach for conventional all-atom simulations. To overcome this challenge, transition path sampling is applied to resolve the kinetic pathways, to characterize the reaction mechanism, and to provide an accurate estimate of the exchange rate. The results reveal that water exchange involves the concreted motion of two exchanging water molecules and the collective rearrangement of all water molecules in the first hydration shell.