2016/03/18 by Jeremy O. Richardson, Cristóbal Pérez, Simon Lobsiger +7 · 2 citations
Chemistry · Physics and Astronomy · #Molecular Spectroscopy and Structure #Advanced Chemical Physics Studies #Quantum, superfluid, helium dynamics
paper · doi:10.1126/science.aae0012
openalex publication_date 2016/03/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
The nature of the intermolecular forces between water molecules is the same in small hydrogen-bonded clusters as in the bulk. The rotational spectra of the clusters therefore give insight into the intermolecular forces present in liquid water and ice. The water hexamer is the smallest water cluster to support low-energy structures with branched three-dimensional hydrogen-bond networks, rather than cyclic two-dimensional topologies. Here we report measurements of splitting patterns in rotational transitions of the water hexamer prism, and we used quantum simulations to show that they result from geared and antigeared rotations of a pair of water molecules. Unlike previously reported tunneling motions in water clusters, the geared motion involves the concerted breaking of two hydrogen bonds. Similar types of motion may be feasible in interfacial and confined water.