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2.3 Basic structure types

NaCl-type

Crystal data

Formula sum NaCl
Crystal system cubic

Space group F m -3 m (no. 225)

Unit cell dimensions a = 5.6250(5) Å
Z 4

Atomic coordinates NaCl

Atom Ox. Wyck. x y z

Na +1 4a 0 0 0
Cl -1 4b 1/2 1/2 1/2

Structural features:
Structural features:
• all octahedral holes of CCP filled, type = antitype

• Na is coordinated by 6 Cl, Cl is coordinated by 6 Na

• One NaCl -octaherdon is coordinated by 12 NaCl -octahedra
6
6
• Connection of octahedra by common edges