Spontaneous Partial Order Driven by Intermolecular Interactions -- Structure and Dynamics of Ice

Water ice's remarkable properties makes it an important material across a range of disciplines with the root-cause of these properties being the combination of covalent and hydrogen bonds forming a long-range lattice of oxygens hosting a disordered yet correlated hydrogen network. The disordered manifold of hydrogen atoms hides strings of 1D order – revealing themselves via optical phonons within a large multi-dimensional neutron scattering dataset. Nearest neighbor intermolecular interactions drive this partial order and hints at a mechanism for ice Ih's transition into ordered ice XI, and potentially extends into the geometry of snowflakes and to other disordered phases. These insights have broader implications for non-periodic systems exhibiting local-symmetry, while enhancing our knowledge of lattice dynamics of this most intriguing material.