crystal (shown opposite) has cell dimensions a, b = 8.276Å
and c =4.027Å (90º, 90º, 90º) and contains
12 water molecules .
A third of these water molecules are more regularly tetrahedral
than the remainder and, thus, experience a differing molecular environment.
In the above structure,
the seven-membered rings involve water molecules above/below each
other such as found at the bottom right.
is metastable within the ice-five phase space.
in this structural diagram the hydrogen bonding is ordered whereas
in reality it is random (obeying the 'ice' rules: two hydrogen atoms
near each oxygen, one hydrogen atom on each O····O bond).