A scheme is described and illustrated in dimension n = 2 for a generalized non-commutative crystallography. It makes use of free groups, their groups of automorphisms, and their geometric representation. The translation group is replaced by a non-commutative group whose elements are paths on a lattice. Finite point groups are preserved, and non-commutative space groups can be defined. Algebraic mechanisms are given which select points for the description of quasicrystals.
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