Distinguish between (i)Hexagonal and monoclinic unit cells (ii) Face−centred and end−centred unit cells.

Distinguish between

(i)Hexagonal and monoclinic unit cells

(ii) Face−centred and end−centred unit cells.

Solution:

(i) Hexagonal unit cell

 
For a hexagonal unit cell,

Monoclinic unit cell

For a monoclinic cell,

  

(ii) Face−centred unit cell

A face−centred unit cell has one constituent particle which is present at each corner and one at the centre of each face.

End−centred unit cell

A end−centred unit cell has one particles at each corners and one at the centre of any

two opposite faces.