Abstract. The space groups of the orthorhombic approximant lattices to the primitive icosahedral quasilattice are classified. There exist three Bravais classes: Pmmm, Cmmm and Immm. The basis vectors of the Bravais lattice of an approximant are parallel to two-, three- and/or fivefold axes of the quasilattice. It is found that there exist many nonsymmorphic space groups with a common Bravais lattice in addition to symmorphic ones. This is because glides commonly appear.

Print publication: Issue 7 (7 April 1992)