title: Hybrid quantum/classical molecular dynamics for a proton transfer reaction coupled to a dissipative bath.
abstract: A hybrid quantum/classical molecular dynamics approach is applied to a proton transfer reaction represented by a symmetric double well system coupled to a dissipative bath. In this approach, the proton is treated quantum mechanically and all bath modes are treated classically. The transition state theory rate constant is obtained from the potential of mean force, which is generated along a collective reaction coordinate with umbrella sampling techniques. The transmission coefficient, which accounts for dynamical recrossings of the dividing surface, is calculated with a reactive flux approach combined with the molecular dynamics with quantum transitions surface hopping method. The hybrid quantum/classical results agree well with numerically exact results in the spatial-diffusion-controlled regime, which is most relevant for proton transfer in proteins. This hybrid quantum/classical approach has already been shown to be computationally practical for studying proton transfer in large biological systems. These results have important implications for future applications to hydrogen transfer reactions in solution and proteins.
authors.affiliation: Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Sharon
authors.initials: S
authors.lastname: Hammes-Schiffer
mesh_terms: D001703:Biophysics / Q000379:methods; D002627:Chemistry, Physical / Q000379:methods*; D003198:Computer Simulation; D004058:Diffusion; D004798:Enzymes / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry; D007700:Kinetics; D015233:Models, Statistical; D008962:Models, Theoretical; D009010:Monte Carlo Method; D011506:Proteins / Q000737:chemistry; D011522:Protons; D011789:Quantum Theory; D012984:Software
chemical_list: D004798:Enzymes; D011506:Proteins; D011522:Protons; D006859:Hydrogen