Summarizing Band Theory of Solids

Summary

• The energy levels of an electron in a crystal can be determined by solving Schrödinger’s equation for a periodic potential and by studying changes to the electron energy structure as atoms are pushed together from a distance.
• The energy structure of a crystal is characterized by continuous energy bands and energy gaps.
• The ability of a solid to conduct electricity relies on the energy structure of the solid.

Glossary

conduction band

above the valence band, the next available band in the energy structure of a crystal

energy band

nearly continuous band of electronic energy levels in a solid

energy gap

gap between energy bands in a solid

semiconductor

solid with a relatively small energy gap between the lowest completely filled band and the next available unfilled band

valence band

highest energy band that is filled in the energy structure of a crystal