Abstract: In this paper, an interactive demonstration program for hydrogen atom energy levels and spectra is designed by using the Wolfram Language. The relevant code is extended to demonstrate the fine structure of hydrogen atom energy levels caused by relativistic effect and spin-orbit coupling effect, and to demonstrate the comparison of energy levels and spectra between different hydrogen-like ions. These programs can be used in interactive demonstration-assisted teaching in atomic physics to help students deepen their understanding of related knowledge.

Key words:  energy levels and spectra, fine structure, interactive demonstration