[kennend3]

None of this is accurate.

Iron will not happily fuse further because this NEEDS energy and where would that energy come from?

"heavier than iron" elements are produced when a star explodes because that collapse produces enormous amounts of energy.

During the collapse, the outer edge of the star is accelerated to something like 20% of the speed of light, that is an ENORMOUS amount of energy slamming down on the core.

Lastly, neutron starts don't produce energy, they are the incompressible remnants of a dead star.

[moloch-hai]

You answer your own question: the energy for further fusion, all the way to neutron degeneracy, is provided by gravitational collapse. The outer layers fusing provide energy for the explosion.

[moloch-hai]

... which, it must be said, is probably more important than gravitation in overcoming nuclear charge repulsion.