Dft Vasp

Hard requirement

The user must provide enough starting context:

• structure input for static / relax
• prerequisite SCF artifacts for dos / band when required

If prerequisites are missing, stop and ask for them.

Routing rules

1. If user requests single-point energy/electronic SCF: route to dft-vasp/static.
2. If user requests geometry optimization: route to dft-vasp/relax.
3. If user requests density of states workflow: route to dft-vasp/dos.
4. If user requests band-structure workflow: route to dft-vasp/band.
5. If intent is ambiguous, ask one focused clarification question before routing.

vaspkit integration

All subskills should use vaspkit for KPOINTS and POTCAR generation rather than manual file creation. This ensures:

• correct pseudopotential selection (recommended variants like Pb_d)
• reproducible k-mesh generation from spacing parameters
• consistent POTCAR ordering matching POSCAR species

Standard workflow:

# Generate KPOINTS + POTCAR in one step (spacing = 0.04 Å⁻¹)
echo -e "102\n1\n0.04" | vaspkit

# Or POTCAR only
echo -e "103" | vaspkit

Prerequisite: ~/.vaspkit must define PBE_PATH (or LDA_PATH) pointing to the VASP pseudopotential library. See dft-vasp/static for detailed vaspkit usage and k-spacing guidelines.

Shared policy for all subskills

• do not invent pseudopotentials
• expose assumptions explicitly
• report unresolved scientific choices
• return handoff-ready task directory
• if execution is requested, hand off to dpdisp-submit

GPUMD / NEP integration

VASP is the most common DFT backend for generating NEP training labels.

• NEP labeling: use dft-vasp/static for single-point energy+force+stress on perturbed structures. Recommended settings: EDIFF = 1e-6, PREC = Accurate.
• Structure relaxation: use dft-vasp/relax to obtain equilibrium geometry before perturbation sampling for NEP.
• Conversion: after VASP runs, convert OUTCAR to NEP extxyz via GPUMD/tools/Format_Conversion/vasp2xyz or dpdata-cli:

  uvx dpdata OUTCAR -i vasp/outcar -O train.xyz -o extxyz
  

• Virial convention: VASP OUTCAR reports stress in kBar. The converter must multiply by cell volume and flip sign to get virial in eV. Always verify.
• Submission: hand off to dpdisp-submit for HPC execution.

Output from router

Provide:

1. selected subskill name
2. why it was selected
3. minimal required inputs still missing (if any)
4. explicit next step (invoke selected subskill)