find out the binding energy of the 2s electron in iron.

The five highest energy peaks in photoelectron spectrum of atomic iron occur at binding energies of 7112, 845, 713.5, 91.3 and 52.7 eV.

1. Allocate these peaks to their appropriate electronic transitions.

2. Apply Slater's rules to find out the binding energy of the 2s electron in iron. How well does this find outd energy agree with experiment?

3. Slater's rules do not differentiate s and p orbital energies. Use the experimental data to find out Zeff for the 2s and 2p electrons in atomic iron. Consider the ionization process as the reaction Qz → Qz+1 + e-, where the ionization potential is the minimum energy needed to remove the electron. This yields the relation IP = E(Qz) - [E(Qz+1) + E(e-)], with the energy of the free electron, E(e-), set to zero, and the energy of each individual species, E(Qz) or E(Qz+1), defined as the total energy of all the electrons bound in Qz or Qz+1, respectively.

4. Using this new approach, apply Slater's rules to find out the binding energy of the 2s electron in iron. Does the new energy agree better with experiment?

5. Why do the two approaches differ in their results?