COMPARISON OF CRYSTAL STRUCTURES
Crystal structure coordination # packing factor close packed directions
Simple Cubic (SC) 6 0.52 cube edges
Body Centered Cubic (BCC) 8 0.68 body diagonal
Face Centered Cubic (FCC) 12 0.74 face diagonal
Hexagonal Close Pack (HCP) 12 0.74 hexagonal side
Diamond 4 ? Body diagonal
1. How about FCC + an atom at the body center?
2. How about NaCl crystal?
Quiz on packing factor:
2015/3/16