What is the coordination number of the simple cubic (SCC) lattice?

• A. 6
• B. 8
• C. 12
• D. 14

Answer: (A)

Coordination number is the count of nearest neighbor lattice points touching a given lattice point. In a simple cubic lattice, lattice points sit at the corners of cubes. From any corner, the closest neighbors lie along the cube edges in the ±x, ±y, and ±z directions. That gives six nearest neighbors in total. So the coordination number is six. Note that other lattice types have different values (for example, eight for body-centered cubic and twelve for face-centered cubic).