Module 1: Structure of Ceramics
  Brief Review of Structure in Materials
 


       1.1.3 Motif and Crystal Structure

  • Crystal structure: a combination of motif and point lattice

  • Motif is defined as a unit or a pattern. For a crystal, it can be an atom, an ion or a group of atoms or ions or a formula unit or formula units. Often it is also called as Basis.

  • When motif replaces points in a periodic point lattice, it gives rise to what is called as a crystal with a defined structure.

Figure 1.3 Formation of a periodic crystal structure