Tungsten bronzes square

FIGURE 5.35 (a) The tetragonal tungsten bronze structure (b) the hexagonal tungsten bronze structure. The shaded squares represent WOe octahedra, which are linked to form pentagonal, square and hexagonal tunnels. These are able to contain a variable population of metal atoms, shown as open circles. 

Figure 3. Representation of a single idealized sheet of the hexagonal tungsten bronze /f-MFr structure. Open circles represent the F ligands close to the plane containing the M atoms (small black spots). MFs octahedra represented by the squares, crossed diagonally, are tilted in the direction indicated by the short arrows. Shaded circles indicate K sites at Cq/4 above or below the plane of the M atoms.

FIGURE 4 12 Tetragonal tungsten bronze structure the circles represent possible metal atom sites and the shaded squares WOs octahedra [4.30]. 

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