The 3+2 dimensional composite structure of the LaSb2Snx
In the refined average structure, based on the strong parent reflections, the tin atoms can’t be described correctly using a 3D model. Note that the periodicities along the b-axis are identical for the two interpenetrating substructures.
The unitcell of the tin substructure (blue). The a- and c-axis of the tin substructure are incomensurate with respect to those of the LaSb2 substructure (in red). To describe both substructures simultaniously you need 5 dimensions in total.