Molecular dance: Water’s collective modes

Ice surfaces are used to assign five resonances in the hydrogen-bonded vibrational spectrum of water. Ice surface experiments are complemented with room temperature matrix isolation experiments providing compelling evidence that the OH vibration of the donor is affected by the environment around the lone pairs, i.e., compelling evidence for the importance of three-body interactions. In addition, longer-range, correlated motion produces a quadrupole at the ice surface.