Packing factor of a nucleus is the ratio of mass defect and the mass number defined as,
[tex] Packing factor=\frac{Actual isotopic mass- Mass number}{Mass number} [/tex]×[tex] 10^{4} [/tex]
Whereas binding energy is the energy that holds the nucleons together in a nucleus. It is equal to the mass defect of the nucleus.
Thus, lower the packing fraction, greater is the binding energy and the nucleus is more stable.
When the binding energy is zero, the isotopic mass is greater than the mass number. In this case, the packing factor of the nucleus is maximum.
