How is the density of states (DOS) computed?

The density of states (DOS) counts the number of electronic states per unit energy at each energy level, integrated over the entire Brillouin zone.

Calculation Procedure

1. Perform a self-consistent DFT calculation with a dense uniform k-point grid
2. Compute eigenvalues at all k-points
3. Histogram the eigenvalues into energy bins
4. Apply Gaussian or Lorentzian broadening to smooth the result

Types of DOS in MatCraft

• Total DOS: Sum of all contributions from all atoms and orbitals
• Element-projected DOS (PDOS): Contribution from each chemical element
• Orbital-projected DOS: Contribution from each orbital type (s, p, d, f)
• Spin-resolved DOS: For magnetic materials, separate curves for spin-up and spin-down channels

Broadening

Raw DOS from a finite k-grid has sharp, noisy features. Gaussian smearing (typically 0.05-0.2 eV width) smooths the DOS for visualization. The choice of smearing width affects the apparent sharpness of peaks but not the integrated quantities.

Practical Uses

• Identifying metallic vs. semiconducting behavior
• Determining orbital character of valence and conduction bands
• Estimating d-band center for catalysis predictions
• Analyzing chemical bonding through orbital overlap