අයනීකරණ ශක්තිය පරමාණුක ක්රමාංකයට එරෙහිව ප්රස්තාරගත කිරීම, eV ඒකක වලින්. The ionization energy gradually increases from the alkali metals to the noble gases. The maximum ionization energy also decreases from the first to the last row in a given column, due to the increasing distance of the valence electron shell from the nucleus. Predicted values are used for elements beyond 104.
Rydberg equation, a calculation that could determine the ionization energies of hydrogen and hydrogen-like elements. This is further elaborated through this site.
Electron affinity, a closely related concept describing the energy released by adding an electron to a neutral atom or molecule.
Lattice energy, a measure of the energy released when ions are combined to make a compound.
Electronegativity is a number that shares some similarities with ionization energy.
Koopmans' theorem, regarding the predicted ionization energies in Hartree–Fock theory.
Ditungsten tetra(hpp) has the lowest recorded ionization energy for a stable chemical compound.
Bond-dissociation energy, the measure of the strength of a chemical bond calculated through cleaving by homolysis giving two radical fragments A and B and subsequent evaluation of the enthalpy change
Bond energy, the average measure of a chemical bond's strength, calculated through the amount of heat needed to break all of the chemical bonds into individual atoms.