About the energy necessary to pull out the closest electron of a atom

[Brunno]

Dear friends,
I was wondering what would be the necessary amount of energy to pull out the closest electron of an iron metal. I read that the energy required for the most distant electrons of the iron metal is about 9 thousand KJ/mol.

Thanks my sages@

 

[Simon Bridge]

For bulk iron?
That would be the work-function ... defining "closest" as the electrons with the least binding energy.

 

[Borek]

Exactly the same energies are involved in Auger effect.