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2.4 More complex structures
Oxides: ReO 3
Crystal data
Formula sum ReO 3
Crystal system cubic
Space group P m -3 m (no. 221)
Unit cell dimensions a = 3.7504(1) Å
Z 1
Atomic coordinates
Atom Ox. Wyck. x y z
Re1 +6 1a 0 0 0 Unit cell
O1 -2 3d 1/2 0 0
Structural features:tructural features:
S
• no close packing (CN (O,O) = 8)
• ReO octahedra connected by six common corners
6
• large cavity in the center of the unit cell
• filled phase (A WO tungsten bronze)
3
x
