Question

In closed packed structure, what is 'ccp' and 'hcp'?

Answer 1

CCP = It is a "cubic closed packing " in which the unit cell has a cube like structure in which all the particles are placed in a horizontal layer (a)and vertical rows (b) while a third layer is placed between the layers to cover an octahedral void between the adjacent square and forms a cube like structure.

HCP = It is a "hexagonal close packing" in which the unit cell makes a hexagon like structure where, all the particles are arranged in such a way that, every next row of particles is placed in depression between the particles of the first row and the third row is aligned vertically with the first row particles.