The movie shows a 1 ps trajectory of a water chain with an added excess proton from ab initio simulations. The proton diffuses readily between the water molecules. The water bond length and bond angle vibrations, which give rise to characteristic infrared spectroscopic features, are visible. For more details and comparison with experimental results from the Heberle group (FU Berlin) see
Orientation of non-spherical protonated water clusters revealed by infrared absorption dichroism.
Jan O. Daldrop, Mattia Saita, Matthias Heyden, Victor A. Lorenz-Fonfria, Joachim Heberle, Roland R. Netz NATURE COMMUNICATIONS (2018) 9:311