Quantum dynamics of proton transfer in the H3O+H2O complex

We have studied the quantum dynamics of proton transfer in the hydrogen-bonded complex H3O+H2O using a previously computed three-dimensional potential energy surface. The two coordinates considered are the distance of the hydrogen atom from the OO midpoint and the OO distance, for a linear OHO geometry. It is shown that a symmetry-breaking external electric field may localize the proton in the region near one of the two oxygen atoms. This initial wave-packet is propagated in time and the probability that the proton could be assigned to one oxygen atom is partitioned in two contributions, arising from the fluxes along the reaction path and along other paths. It is shown that, depending on the strength of the electric field, the two contributions may cooperate or become antagonists.