Module 1: Structure of Ceramics
  Structures based on HCP Packing of Ions
 

      
       1.10.4 Lithium Niobate Structure

  • Structure is similar to Al2O3 except that Al sub-lattice is substituted in an ordered manner by Li and Nb ions in the same layer unlike in alternating layer in Fe2O3.

  • The parent compound LiNbO3 is ferroelectric in nature and hence, is technologically important.

  • LiNbO3 also has highly anisotropic refractive index and it shows birefringence which is changeable by electric field.

  • Such materials are used in electro-optic devices.

Figure 1.44 Atomic arrangement of a layer in LiNbO3 structure

Figure 1.45 Structure on {10-10} plane in LiNbO3