NaCl – Rocksalt, Halite, Sodium chloride: Interactive 3D Structure

– 6:6 (Oh)

Cl^– with Na⁺ in all Oh holes

Polyhedra – Edge-sharing
and octahedra

All octahedral holes in a cubic close packing are occupied by counterions.
Both ions show octahedral coordination (CN = 6).

(a) The rock-salt structure and (b) its projection representation. Note the relation of this structure to the fcc structure  with an atom in each octahedral hole.

Related Structure: Nickel Arsenide (NiAs)