Proton conduction along a chain of water molecules. Development of a linear model and quantum dynamical investigations using the multiconfiguration time-dependent Hartree method

Abstract

Proton transfer along a chain of water molecules is discussed. A linear model for such a chain is developed and its parameters are determined by comparison to quantum chemistry calculations. Fully quantum mechanical dynamical simulations on the translocation process are performed for different chain lengths, with up to five water molecules. We found that tunneling is important for the proton-transfer process. Furthermore, translocation is accomplished through a strongly correlated motion involving both hydrogen and oxygen atoms. An approximate treatment, which limits or even neglects this correlation, may lead to severely incorrect results.