Lesson 1, Topic 1
In Progress

Derivatives of FCC Lattices

Abdulaziz July 26, 2020

In this Topic:

  • Diamond structure (Si, Ge& Diamond)
  • Zinc-Blende Structure
  • Sodium Chloride (Rocksalt) structure

Diamond structure (Si, Ge& Diamond)

  • Can be viewed as two interpenetrating fcc lattices displaced by ¼, ¼, ¼

Zinc-Blende Structure

  • Identical to diamond lattice but sites are occupied by two different atoms Example: GaAs, ZnS, AlAs, InP

8 atoms per cell:

Sodium Chloride (Rocksalt) structure

  • Example: AgCl, CaO, MgO, KF, KCl, LiCl

Na+at corners: (8 ×1/8) = 1,
Na+at face centres (6 ×1/2) = 3
Clat edge centres (12 ×1/4) =3
Clat body centre = 1
Unit cell contents are 4(Na+) and4(Cl)

Summary of FCC lattice

One crystallattice + different basis → different crystal structures!