Figure 2. The experimental and calculated IE value of atoms (H-Xe)

From

Modeling of Ionization Energy of Elements Using Hartree-Fock Method: An Introduction to Computational Quantum Chemistry for Undergraduate Students

Krishnamohan G P, Thomas Mathew, Simi Saju, James T. Joseph

World Journal of Chemical Education. 2017, 5(3), 112-119 doi:10.12691/wjce-5-3-6