Answer:
The empirical formula of the compound would be 
Explanation:
The A ions are in the body center position and at each corner .
There are 8 faces of the cube and 1 corner is also shared by another 7 cubic unit.
Then number of A ion in a cubic unit = 
The Z ions are on each face of the cubic unit :
There are 6 faces of the cube and 1 face is shared by another cubic unit.
Then number of Z ions in a cubic unit = 
The structural formula of the cubic lattice is =
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
The empirical formula of the compound would be 