CHECKPOINT FD
Warning: Not yet released!
This page contains information about a feature that will be available in a future release of VASP. In other words, currently you cannot use it even with the latest version of VASP. The information may change significantly until it is released.
CHECKPOINT = [string]
Description: CHECKPOINT enables a finite-differences calculation to be restarted or split up into displacements
| Mind: Available as of VASP 6.6.0 |
Important: This is currently only available for IBRION = 6.
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Phonon (or vibrational) modes can be calculated using finite differences. A series of displacements are made, DFT calculations performed on each of these, and then the second-order force computed and the dynamical matrix is constructed, from which the phonon modes and frequencies are calculated. Using CHECKPOINT (with IBRION = 6), it is possible to restart a calculation that crashed from the last displacement. The displacements are written to the vaspcheck.h5 file.
CHECKPOINT = continue- The vaspcheck.h5 file is read if it exists and the calculation continues where it left off. Otherwise, vaspcheck.h5 is created and written to. In both cases, the calculation will finish with the vaspcheck.h5 file fully completed. A new continuation job will then simply do a single SCF for the equilibrium and read all the data from the file. This mode also detects if the calculation is a single VASP calculation or if it was split into separate pieces. If it was split, all the calculations need to have finished or an error is produced.
CHECKPOINT = reset- (default)- Overwrite the vaspcheck.h5 file and start from scratch. The rest is identical to continue.
CHECKPOINT = legacy- Behavior of the code before this MR. No checkpoint file is written.
CHECKPOINT = prepare- The vaspcheck.h5 file is created/overwritten and populated with meta data. For each displacement, a CONTCAR_disp-N file is written containing the displacement pattern of displacement N. VASP then stops after one SCF. To run this displaced calculation, create a directory disp-N, copy the corresponding CONTCAR file into it and rename it to POSCAR. Then run the calculation with checkpoint=single.
CHECKPOINT = single- This mode is used to run the individual single-shot VASP calculations produced by checkpoint=prepare. This also produces a vaspcheck.h5 file in the corresponding directory that contains the displaced data.