The average binding energy

[thephy]

Why is the average binding energy of iron is biggest?
Are there some theories about it?

[theFuture]

Weizsacker semi-empirical mass formula.

http://www2.sjsu.edu/faculty/watkins/semiempirical.htm

[Pieter Kuiper]

Summary: smaller nuclei have relatively more nucleons on the surface (these are not bound by neighbours on all sides), and larger nuclei have a stronger Coulomb repulsion. There has to be a maximum somewhere, and this happens to be at iron.

[thephy]

Thank you.