static

name	static
description	Prepare CP2K single-point (static) task inputs from a user-provided structure and essential DFT settings. Use when the user needs total-energy/electronic SCF evaluation with explicit CP2K basis/potential and SCF controls.
compatibility	Requires a user-provided structure, suitable CP2K basis/potential files, and runnable CP2K environment.
license	GPL-3.0-only
catalog-hidden	true
metadata	{"author":"qqgu","version":"0.2.0","repository":"https://github.com/cp2k/cp2k"}

CP2K Static (Subskill)

Scope

This skill prepares single-point RUN_TYPE ENERGY tasks only. It generates the CP2K input file, the basis/potential mapping, and CP2K_DATA_DIR guidance. It does not submit or execute jobs — hand off to dpdisp-submit.

Must provide

• structure input (Cartesian Å coordinates and a CELL block)
• XC functional (PBE, BLYP, SCAN, PADE/LDA, ...)
• basis + GTH pseudopotential pair per element (must match the functional)
• SCF convergence policy (EPS_SCF, MAX_SCF, OT vs diagonalization)
• MGRID/CUTOFF in Ry (plane-wave auxiliary grid for GPW)
• charge / multiplicity / LSD flag for open-shell species

Usually should be explicit

Tag	Role	Recommended
CUTOFF	auxiliary grid, Ry	400 for MOLOPT-SR-GTH, 600 for light atoms + accurate forces
REL_CUTOFF	ratio cutoff	60 (default); raise if grid warning appears
NGRIDS	multigrid levels	4 (default)
EPS_DEFAULT	global QS tolerance	1.0E-10 production, 1.0E-8 screening
EPS_SCF	inner SCF stop	1.0E-6 production
SCF_GUESS	starting density	ATOMIC (cold start), RESTART (chained runs)
OT	orbital transformation	Always use for insulators (gapped). DIIS + FULL_SINGLE_INVERSE preconditioner is the robust default.
OUTER_SCF	outer loop for OT	MAX_SCF = 10, EPS_SCF = 1E-6
PRINT_LEVEL	verbosity	LOW (routine), MEDIUM (debug)

OT rules of thumb:

• Molecules / insulators: always prefer OT — faster, no diagonalization.
• Metals / small-gap systems: OT cannot handle fractional occupations. Use traditional diagonalization with &SMEAR and ADDED_MOS.
• Open-shell: set LSD .TRUE. and give a MULTIPLICITY hint.

Basis / potential matching rule

MOLOPT-SR-GTH basis sets are optimized per functional. Pair rules:

Basis family	Potential family	Functional
DZVP-MOLOPT-SR-GTH, TZV2P-MOLOPT-GTH	GTH-PBE-qN	PBE, PBE0, BLYP, SCAN
DZVP-GTH-PADE, DZV-GTH-PADE	GTH-PADE-qN	LDA / Pade only
DZVP-MOLOPT-SR-GTH	GTH-BLYP-qN	BLYP (if strict matching is desired)

Never mix a PADE pseudopotential with a PBE basis, or vice versa — the valence electron count still works but forces and energies become inconsistent with the functional.

Data path: the distribution ships BASIS_MOLOPT, GTH_POTENTIALS, BASIS_SET, POTENTIAL under $CP2K_DATA_DIR (typically $CP2K_PREFIX/share/cp2k/data). Either set CP2K_DATA_DIR in the environment or give an absolute BASIS_SET_FILE_NAME path in the input.

Concrete example — H₂O single-point (PBE, DZVP-MOLOPT-SR-GTH)

Anchored on the upstream CP2K regression test tests/QS/regtest-gpw-1/H2O-noheader.inp with the modern MOLOPT basis and PBE functional (the CP2K howto:static_calculation reference setup).

Task directory:

H2O_scf/
├── h2o.inp
└── (output: H2O-1.restart, H2O-1_0.wfn, h2o.out)

h2o.inp:

&GLOBAL
  PROJECT H2O
  PRINT_LEVEL LOW
  RUN_TYPE ENERGY
&END GLOBAL

&FORCE_EVAL
  METHOD QS
  &DFT
    BASIS_SET_FILE_NAME BASIS_MOLOPT
    POTENTIAL_FILE_NAME GTH_POTENTIALS
    &MGRID
      CUTOFF 400
      REL_CUTOFF 60
      NGRIDS 4
    &END MGRID
    &QS
      EPS_DEFAULT 1.0E-10
    &END QS
    &SCF
      EPS_SCF 1.0E-6
      MAX_SCF 50
      SCF_GUESS ATOMIC
      &OT
        MINIMIZER DIIS
        PRECONDITIONER FULL_SINGLE_INVERSE
      &END OT
      &OUTER_SCF
        EPS_SCF 1.0E-6
        MAX_SCF 10
      &END OUTER_SCF
    &END SCF
    &XC
      &XC_FUNCTIONAL PBE
      &END XC_FUNCTIONAL
    &END XC
  &END DFT
  &SUBSYS
    &CELL
      ABC 10.0 10.0 10.0
      PERIODIC XYZ
    &END CELL
    &COORD
      O   0.000000    0.000000   -0.065587
      H   0.000000   -0.757136    0.520545
      H   0.000000    0.757136    0.520545
    &END COORD
    &KIND H
      BASIS_SET DZVP-MOLOPT-SR-GTH
      POTENTIAL GTH-PBE-q1
    &END KIND
    &KIND O
      BASIS_SET DZVP-MOLOPT-SR-GTH
      POTENTIAL GTH-PBE-q6
    &END KIND
  &END SUBSYS
&END FORCE_EVAL

Run (single-thread SMP binary):

export CP2K_DATA_DIR=$CONDA_PREFIX/share/cp2k/data   # or path to your build
cp2k.ssmp -i h2o.inp -o h2o.out

Physical sanity checks after the run

1. grep 'SCF run converged' h2o.out — must report SCF run converged in N steps. For the H₂O example above expect ~16 inner steps (OT + DIIS) and a single outer SCF iteration.
2. grep 'ENERGY| Total' h2o.out — total FORCE_EVAL ( QS ) energy. For the H₂O example (PBE + DZVP-MOLOPT-SR-GTH, CUTOFF 400, 10 Å cubic box) the reference value is −17.2196 Hartree ≈ −468.43 eV. A drift

   1 mHa usually means CUTOFF is too low or the basis/functional do not match.

3. grep 'Number of electrons' h2o.out — must equal the GTH valence sum (H₂O: 2 × 1 + 6 = 8). Mismatches indicate a wrong -qN potential choice.
4. grep 'REL_CUTOFF' h2o.out and check the printed grid distribution — if the finest grid holds < 50 % of the Gaussians, raise CUTOFF (not REL_CUTOFF).

Known build traps

• OT + metal (small-gap Cu, graphene, ...) fails to converge or converges to a wrong density. Switch to &SCF / DIAGONALIZATION with &SMEAR and set ADDED_MOS to 2 × occupied.
• Periodic jobs with a too-small cell for a molecule (< 6 Å vacuum) have significant periodic-image interaction — for dipolar solutes use POISSON / PERIODIC NONE / PSOLVER MT or grow the box.
• BASIS_SET_FILE_NAME using a relative name requires CP2K_DATA_DIR to point at the directory that contains the file. A common error is to point it at the parent share/cp2k-<version> instead of share/cp2k/data; the error message prints the failed path literally, which is the quickest way to diagnose.
• Hybrid functionals (PBE0, HSE06) need auxiliary fit basis (FIT3/FIT4 in BASIS_ADMM) and the &AUXILIARY_DENSITY_MATRIX_METHOD block — out of scope for the plain-GGA static skill.

Expected output

1. static-task directory with .inp file and data-dir guidance
2. basis / potential mapping summary (must justify each pair)
3. settings summary (CUTOFF rationale, OT vs DIAG choice)
4. sanity-check checklist (SCF steps, total energy, electron count)
5. handoff note to dpdisp-submit