As indicated by the large error limits on the angles, the dimer executes large amplitude motions.

Such motions are characteristic of "floppy" molecules which are able to change their geometry with relatively little change in energy.

In this case the large amplitude motion involves the tilting of each H₂O unit relative to the other.

The observed hydrogen bond energy is 22.6 (+/- 3.0) kJ mol^-1 with respect to two free H₂O molecules.

Note that this is significantly larger than the bond energy in a van der Waals molecule.