Plzz explain the difference between edge centred and end centered and also give their the atoms /ions present in their one unit cell

Dear student,

In the case of end centered unit cell, the atoms are present in the two opposite faces and in the corners but in case of edge centered unit cell, the atoms are present in the corners and the center of all edges in the cubic unit cell.

The number of atoms in an end-centered unit cell is 2. This is because, in each end centered unit cell, there are 8 atoms at the eight corners of the cube, and one atom each is present at the center of any two opposite faces. 

Total number of atoms in one unit cell

= 8 corner atoms X (1/8) atom per unit cell + 2 face-centered atoms X (1/2) atom per unit cell

= 1 + 1

=2



Regards