For a material having FCC crystal cell structure, write the expressions for Planar atomic density in planes (0,0,1) and (1,1,0) in terms of atomic radius ‘r’ and calculate for Copper in gms/cm3 . Why metal shows directional nature of properties at atomic level whereas its bulk measured properties are isotropic in nature.

For a material having FCC crystal cell structure, write the expressions for Planar atomic density in planes (0,0,1) and (1,1,0) in terms of atomic radius ‘r’ and calculate for Copper in gms/cm3 . Why metal shows directional nature of properties at atomic level whereas its bulk measured properties are isotropic in nature.