The f orbitals are buried even more deeply, and adjacent inner transition metals show almost no difference in chemical behavior.

The electronic configuration of any atom, and the structure of the periodic table, both are consequences of the energy-level diagram obtained from spectroscopy and wave mechanics. The idealized electron arrangement of any atom can be worked out from its place in the periodic table.

Example 1:
Tin (Sn) is found in the p column of the representative elements, in row five of the periodic table. What is its electronic structure?

Solution:
Building up the atom, following the orbital-filling diagram available on page 12, until 5p is reached, you can see that the electronic structure of the tin atom must be

Sn:

This can be simplified by using the symbol [Kr] to represent the inner core of electrons of the noble gas krypton:

Kr: