O2Si
Schlenker, J.L.Dwyer, F.G.Jenkins, E.E.Kokotailo, G.T.Rohrbaugh, W.J.Meier, W.M.
Nature (London) (1981) 294, 340-342
a=19.36Å b=19.36Å c=19.36Å
α=90° β=90° γ=90°