The crystallographic restriction theorem in its basic form was based on the observation that the rotational symmetries of a crystal are usually limited to 2-fold, 3-fold, 4-fold, and 6-fold. However, quasicrystals can occur with other diffraction pattern symmetries, such as 5-fold; these were not discovered until 1982 by Dan Shechtman.
quasicrystals occurs with 5-fold.
( z1 product-of :op 5 :op ( z2 small-molecule :name ( z3 name :op "quasicrystals" ) ) )