checkforce

The checkforce script checks the convergence of geometry optimisations in VASP.

Synopsis

checkforce [-h] [-o OUTCAR] [-c CONVERGENCE] [-v | -a]

Description

Analyses forces from a VASP OUTCAR file and reports convergence statistics. By default, reports statistics for the last ionic step only.

Options

-h, --help

Show help message and exit.

-o OUTCAR, --outcar OUTCAR

The filepath of the OUTCAR file to be parsed. Default is “OUTCAR”.

-c CONVERGENCE, --convergence CONVERGENCE

Set force convergence threshold. Default is to read the convergence from the OUTCAR file (EDIFFG).

-v, --verbose

Verbose output. Show convergence status for all atoms in the last ionic step.

-a, --all

Print summary data for every ionic step.

Note

The -v and -a options are mutually exclusive.

Examples

Check convergence using default OUTCAR:

checkforce

Check with a specific OUTCAR file:

checkforce -o path/to/OUTCAR

Set a custom convergence threshold:

checkforce -c 0.01

View summary for all ionic steps:

checkforce -a
Output shows:

  • Max Force: Maximum force magnitude across all atoms

  • Non-opt: Number of atoms not yet converged

  • Mean Excess: Mean excess force above convergence threshold

Verbose output for last step:

checkforce -v

Output Format

Default output (last step only):

remainder:  0.001234
maximum:    0.023456
non-opt:    3 / 24

All steps output (-a flag):

Max Force      Non-opt        Mean Excess
0.156789       12             0.012345
0.089012       8              0.006789
0.023456       3              0.001234
0.009876       0              0.000000