Question

What is the coordination number of NaCl crystal structure?

Answer 1

In the NaCl crystal structure:

• Each Na⁺ ion is surrounded by 6 Cl⁻ ions.
• Each Cl⁻ ion is also surrounded by 6 Na⁺ ions.
• This arrangement is known as a 6 : 6 coordination.

Coordination number of NaCl is 6. This is due to the face-centred cubic (FCC) arrangement of Cl⁻ ions, with Na⁺ ions occupying all the octahedral voids, resulting in a highly symmetrical and stable crystal structure.