Terminal output

The standard output of VASP has several sections and can contain important warnings and error messages.

The header

The header has a few sections, that may or may not get printed depending on the calculation.

No of nodes, MPI ranks, OpenMP threads, and parallelization

The first output details rank, threading, and parallelization information. E.g with OpenMP threading:

running   16 mpi-ranks, with    4 threads/rank, on    1 nodes
distrk:  each k-point on    4 cores,    4 groups
distr:  one band on    1 cores,    4 groups

or without OpenMP threading, but NCORE set:

running   16 mpi-ranks, with    1 threads/rank, on    1 nodes
distrk:  each k-point on    4 cores,    4 groups
distr:  one band on    2 cores,    2 groups

Version number, build date, and executable type

Note that both the standard and the noncollinear version print out "complex", while the gamma-only version prints "gamma-only": vasp_std and vasp_ncl:

vasp.6.4.3 19Mar24 (build Sep 03 2024 17:30:01) complex

vasp_gam:

vasp.6.5.0 16Dec24 (build Feb 28 2025 14:30:48) gamma-only

Structure information

POSCAR found type information on POSCAR CoSiTi
POSCAR found :  3 types and       4 ions

ScaLAPACK

This line is present if VASP is installed with ScaLAPACK, which is a requirement for VASP 6.

scaLAPACK will be used

LDA part of correlation

The following line prints the implementation selected for the LDA XC energy. E.g.:

LDA part: xc-table for (Slater+PW92), standard interpolation

or

LDA part: xc-table for (Slater(with rela. corr.)+CA(PZ))
, standard interpolation

Reading the WAVECAR header

If a WAVECAR is present, the header is read now

found WAVECAR, reading the header

If the no of k-points changed, a warning is printed here

number of k-points has changed, file:    20 present:     8
trying to continue reading WAVECAR, but it might fail

Warning: In the case a WAVECAR is read in, but the number of k-points NK1 has changed to NK2, the orbitals of the last k-point of the WAVECAR will be used for all remaining k-points if NK2>NK1. If NK2<NK1, the first NK2 k-points from the WAVECAR will be mapped to the new k-points. In both cases the coordinates of k-points are not considered. Thus, if the no of k-points changes, it is not recommended to restart from a WAVECAR, but from a CHARGCAR file.

Input file check

If the input files POSCAR, INCAR, and KPOINTS are consistent, the following line is printed

POSCAR, INCAR and KPOINTS ok, starting setup

FFT planning

FFT: planning ... GRIDC
FFT: planning ... GRID_SOFT
FFT: planning ... GRID

Reading WAVECAR and/or CHGCAR

Depending on the availability of the files and the setting of ISTART and ICHARG, the WAVECAR and/or CHGCAR are read now.

reading WAVECAR
the WAVECAR file was read successfully
charge-density read from file: unknown

If the no of bands increased, this is printed

reading WAVECAR
random initialization beyond band           13
the WAVECAR file was read successfully

For ISPIN = 2 the magnetization density can also be read from CHGCAR

reading WAVECAR
the WAVECAR file was read successfully
charge-density read from file: GaAs                                    
magnetization density read from file 1

The body

After the line

entering main loop

the body of the stdout begins. It is essentially equivalent to the OSZICAR file, thus the meaning of the columns and numbers printed is explained on that page.

Error and warning messages

Errors with the input file will be printed to stdout, and VASP will terminate immediately. E.g. Template:TAGOKPAR.TRUE. will result in:

 -----------------------------------------------------------------------------
|                                                                             |
|     EEEEEEE  RRRRRR   RRRRRR   OOOOOOO  RRRRRR      ###     ###     ###     |
|     E        R     R  R     R  O     O  R     R     ###     ###     ###     |
|     E        R     R  R     R  O     O  R     R     ###     ###     ###     |
|     EEEEE    RRRRRR   RRRRRR   O     O  RRRRRR       #       #       #      |
|     E        R   R    R   R    O     O  R   R                               |
|     E        R    R   R    R   O     O  R    R      ###     ###     ###     |
|     EEEEEEE  R     R  R     R  OOOOOOO  R     R     ###     ###     ###     |
|                                                                             |
|     Error reading item KPAR from file INCAR.                                |
|     Error code was IERR= 5 ... .                                            |
|                                                                             |
|       ---->  I REFUSE TO CONTINUE WITH THIS SICK JOB ... BYE!!! <----       |
|                                                                             |
 -----------------------------------------------------------------------------

If the problem is considered less severe, VASP will continue with the execution, but can display a warning. E.g. the KPOINTS file is missing and KSPACING is not set in the INCAR file VASP will execute with a default, quite corse, mesh:

 -----------------------------------------------------------------------------
|                                                                             |
|           W    W    AA    RRRRR   N    N  II  N    N   GGGG   !!!           |
|           W    W   A  A   R    R  NN   N  II  NN   N  G    G  !!!           |
|           W    W  A    A  R    R  N N  N  II  N N  N  G       !!!           |
|           W WW W  AAAAAA  RRRRR   N  N N  II  N  N N  G  GGG   !            |
|           WW  WW  A    A  R   R   N   NN  II  N   NN  G    G                |
|           W    W  A    A  R    R  N    N  II  N    N   GGGG   !!!           |
|                                                                             |
|     The requested file  could not be found or opened for reading            |
|     k-point information. Automatic k-point generation is used as a          |
|     fallback, which may lead to unwanted results.                           |
|                                                                             |
 -----------------------------------------------------------------------------

Missing information on magnetic moments will result in, probably the wrong, automatic ferromagnetic initialization:

 -----------------------------------------------------------------------------
|                                                                             |
|           W    W    AA    RRRRR   N    N  II  N    N   GGGG   !!!           |
|           W    W   A  A   R    R  NN   N  II  NN   N  G    G  !!!           |
|           W    W  A    A  R    R  N N  N  II  N N  N  G       !!!           |
|           W WW W  AAAAAA  RRRRR   N  N N  II  N  N N  G  GGG   !            |
|           WW  WW  A    A  R   R   N   NN  II  N   NN  G    G                |
|           W    W  A    A  R    R  N    N  II  N    N   GGGG   !!!           |
|                                                                             |
|     You requested a magnetic or noncollinear calculation, but did not       |
|     specify the initial magnetic moment with the MAGMOM tag. Note that      |
|     a default of 1 will be used for all atoms. This ferromagnetic setup     |
|     may break the symmetry of the crystal, in particular it may rule        |
|     out finding an antiferromagnetic solution. Thence, we recommend         |
|     setting the initial magnetic moment manually or verifying carefully     |
|     that this magnetic setup is desired.                                    |
|                                                                             |
 -----------------------------------------------------------------------------

Tip: It is always a good idea to check the stdout (or OUTCAR) for warning messages after a calculation finishes. Often a small oversite can lead to plausible, but incorrect results.