Category:Density of states

The electronic density of states (DOS) describes how many electronic states are available at a given energy. It is a useful tool for analyzing the electronic structure of materials, identifying band gaps, and distinguishing between metallic and insulating behavior. The DOS can also reveal the contribution of different atoms and orbitals to the electronic states.

In VASP, the density of states is typically calculated after a self-consistent calculation using a dense k-point mesh. The DOS is written to the DOSCAR file, while projected contributions from atoms and orbitals can be obtained using tags such as LORBIT. A separate non-self-consistent calculation with a denser k-point grid is often recommended for smoother DOS curves.

For non-spin-polarized systems, the DOS is identical for both spin channels. Silicon in the diamond structure is a typical example of a nonmagnetic semiconductor, where the DOS shows a band gap between the occupied valence states and the empty conduction states.

For spin-polarized systems, the spin-up and spin-down channels can differ significantly. In antiferromagnetic NiO, the DOS reflects the magnetic ordering and the unequal occupation of the spin channels, while still showing an insulating band gap.