Water cluster

One line of research uses graph invariants for generating hydrogen bond topologies and predicting physical properties of water clusters and ice.

The utility of graph invariants was shown in a study considering the (H2O)6 cage and (H2O)20 dodecahedron, which are associated with roughly the same oxygen atom arrangements as in the solid and liquid phases of water.

[19] Experimental study of any supramolecular structures in bulk water is difficult because of their short lifetime: the hydrogen bonds are continually breaking and reforming at timescales faster than 200 femtoseconds.

[21][22] The experimental detection and characterization of the clusters has been achieved by spectroscopy - far-infrared (FIR)[23] and vibration-rotation-tunneling (VRT)[24] - and by H-NMR[25][26] and neutron diffraction.

[27] The hexamer is found to have planar geometry in liquid helium, a chair conformation in organic solvents, and a cage structure in the gas phase.

[33] In another model, bulk water is built up from a mixture of hexamer and pentamer rings containing cavities capable of enclosing small solutes.