This page describes the advanced workflow of using the VASP2WANNIER90 interface to generate Wannier functions.

Please make sure you understand the basic workflow.

Wannierization options

• Write UNK file
  • unformatted UNK
  • formatted UNK
• Control AMN and MMN

Write UNK files

unformatted UNK files

-keywords needed:

ISTART = 1
ICHARG = 2
LWANNIER90 = .TRUE.
LWRITE_UNK = .TRUE.
LUNK_FMTED = .FALSE.

• files needed:
  • wannier90.win
  • WAVECAR
  • CHGCAR
  • INCAR
  • KPOINTS
  • POSCAR
  • POTCAR

The wannier90.win file should at least contain:

num_wann        =  ??

begin projections
??
end projections

ISTART=1 and ICHARG=2 tell VASP to read in the Bloch wavefunctions and charge density files. LWANNIER90=.TRUE. tells VASP to run the interface with default specs. LWRITE_UNK = .TRUE. tells VASP to write periodic part of the wavefunctions (UNK files) LUNK_FMTED = .FALSE. tells VASP to write unformatted UNK files.

formatted UNK files

• keywords needed:

ISTART = 1
ICHARG = 2
LWANNIER90 = .TRUE.
LWRITE_UNK = .TRUE.
LUNK_FMTED = .TRUE.

• files needed:
  • wannier90.win
  • WAVECAR
  • CHGCAR
  • INCAR
  • KPOINTS
  • POSCAR
  • POTCAR

The wannier90.win file should at least contain:

num_wann        =  ??

begin projections
??
end projections

ISTART=1 and ICHARG=1 tell VASP to read in the Bloch wavefunctions and charge density files. LWANNIER90=.TRUE. tells VASP to run the interface with default specs. LWRITE_UNK = .TRUE. tells VASP to write periodic part of the wavefunctions (UNK files) LUNK_FMTED = .TRUE. tells VASP to write formatted UNK files.

After the job is done, there should be a block in the stdout look like:

 *---------------------------------------*
 *             VASP2WANNIER90            *
 *---------------------------------------*
 *         No spin polarization          *
 *            MMN calculated.            *
 *          Projection   1 done.         *
 *          Projection   2 done.         *
 *          Projection   3 done.         *
 *          Projection   4 done.         *
 *          Projection   5 done.         *
 *          Projection   6 done.         *
 *          Projection   7 done.         *
 *          Projection   8 done.         *
 *          Projection   9 done.         *
 *          Projection  10 done.         *
 *          Projection  11 done.         *
 *          Projection  12 done.         *
 *            AMN calculated.            *
 *            EIG written.               *
 *---------------------------------------*

And you should have:

• UNKxxxxx.1 in your directory.

Control AMN and MMN

-keywords needed:

ISTART = 1
ICHARG = 2
LWANNIER90 = .TRUE.
LCALC_MMN  = .FALSE.
LCALC_AMN  = .FALSE.
LWRITE_MMN = .FALSE.
LWRITE_AMN = .FALSE.

• files needed:
  • wannier90.win
  • WAVECAR
  • CHGCAR
  • INCAR
  • KPOINTS
  • POSCAR
  • POTCAR

The wannier90.win file should at least contain:

num_wann        =  ??

begin projections
??
end projections

ISTART=1 and ICHARG=1 tell VASP to read in the Bloch wavefunctions and charge density files. LWANNIER90=.TRUE. tells VASP to run the interface with default specs. LCALC_MMN = .FALSE. tells VASP to NOT to compute the MMN matrix. LCALC_AMN = .FALSE. tells VASP to NOT to write the MMN matrix. LWRITE_MMN = .FALSE. tells VASP to NOT to compute the AMN matrix. LWRITE_AMN = .FALSE. tells VASP to NOT to write the AMN matrix.

After the job is done, there should be a block in the stdout look like:

 *---------------------------------------*
 *             VASP2WANNIER90            *
 *---------------------------------------*
 *         No spin polarization          *
 *---------------------------------------*

and you should have NO new files in you directory. (Because we've disabled everything)

Additional blocks is still added to the wannier90.win file.