Close Packing FCC / BCC / HCP

This interactive simulator explores Close Packing FCC / BCC / HCP in Chemistry. Coordination numbers, maximal packing η, schematic ABC vs AB stacking beside a BCC cubic cell. Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.

Who it's for: Suited to beginners and first exposure to the topic. Typical context: Chemistry.

Key terms

  • close
  • packing
  • fcc
  • bcc
  • hcp
  • close packed lattices
  • chemistry

How it works

FCC and HCP are two ways to stack close-packed planes with the same coordination (12) and maximal packing fraction η = π√2/6. BCC is denser than simple cubic but not close-packed (η = π√3/8, CN = 8).

Key equations

ABC stacking of hexagonal close-packed planes (…ABCABC…).