The Bang Gap measures the finite energy difference between the highest occupied and lowest unoccupied energy levels in, respectively, the valence and conduction bands of a semiconducting or insulating material 1.
Direct and Indirect Band Gaps¶
Two types of band gap are possible: direct and indirect 2. The latter is always computed on our platform, and is equivalent to the former for the direct gap semiconductors.
In case the material is of indirect-gap nature, the pair of k-vectors linking the corresponding minimal energy difference is indicated. Otherwise, for direct-gap semiconductors, the two types of gap are presented as being equivalent and being both located across the Gamma point.
The JSON schema and an example representation for this property can be found here.