Term: bandgap energy, \(E_{\text{g}}\)
https://doi.org/10.1351/goldbook.B00593

Definition:
The energy difference between the bottom of the conduction band and the top of the valence band in a semiconductor or an insulator.

Related Terms:
1) conduction band (http://doi.org/10.1351/goldbook.C01244).
2) valence band (http://doi.org/10.1351/goldbook.V06589).
3) semiconductor (http://doi.org/10.1351/goldbook.S05591).
4) fermi level (http://doi.org/10.1351/goldbook.F02341).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2229 (https://doi.org/10.1351/pac199668122223)

Citation: 'bandgap energy, \(E_{\text{g}}\)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.B00593

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