CONTROL

The CONTROL section holds general, job-wide settings that are not tied to a specific computational stage: output verbosity and checkpoint I/O. It is the home for future general-purpose keywords.

CONTROL
  PrintLevel       Normal          # Minimal / Normal / Verbose / Debug
  WriteCheckpoint  True
  CheckpointName   water_opt.oqw
END

Keywords

KeywordValuesDefaultDescription
PrintLevelMinimal, Normal, Verbose, DebugNormalOutput verbosity.
WriteCheckpointTrue / FalseTrueWrite a binary checkpoint at the end of the section.
CheckpointNamefile name or path<input>.oqwCheckpoint file name. Relative names are placed next to the input file.
ReadCheckpointTrue / False / pathFalseRead a checkpoint at the start. A bare True reads the most recent one; a path reads that file.
ReadCheckpointNamefile name or pathExplicit checkpoint to read (takes precedence over ReadCheckpoint).

Checkpoint contents

Every section with WriteCheckpoint True (the default) writes a binary (bincode) checkpoint capturing:

  • Final geometry (the optimized geometry for Opt, otherwise the input geometry)
  • Molecular orbitals (coefficients and energies)
  • Hessian, when a frequency calculation was run
  • SCF convergence info (energy components, iterations, convergence flag)
  • Basis-set info (name and full shell definition)

In a multi-section run, each checkpoint file holds only the data of the latest section that wrote it.

Default checkpoint name

When CheckpointName is omitted, the file is named after the input's base name with an .oqw extension (e.g. water.inpwater.oqw), written next to the input file.