The energy difference between two allowed ranges of electron energy in a solid; especially the difference between the energies of the valence band and the conduction band.(noun)
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Use "bandgap" in a sentence
"The indirect bandgap occurs when the maximum valence point and minimum conduction point are not aligned on the same wave vector."
"The bandgap is the difference between the maximum energy point in the valence band and the minimum point in the conduction band."
"The direct bandgap occurs when these maximum and minimum points are aligned along the same wave vector."