A 3-D cubic unit cell contains four atoms whose centers are positioned halfway up along each of the vertical cell edges and one atom each centered in the middle of the top and bottom faces.
(a) How many atoms are there per unit cell (atoms actually inside the unit cube)?
(b) Make a sketch (as best you can) of the lattice characterized by the part (a) unit cell. Use dots to represent the atoms and include at least three parallel plancs of atoms.
c) What is the name of the standard unit cell used to characterize the lattice sketched in part (b)?