### VASP + WANNIER90 + spin orbit coupling

Posted:

**Tue Feb 05, 2019 9:25 am**Hi all,

I have a question concerning the combination of VASP and WANNIER90.

My aim is to calculate Hamiltonian Matrix elements in the Wannier function basis for different materials with spin orbit coupling.

As an example let's take mercury telluride (HgTe).

The vasp calculations work fine, but when it comes to the Wannier90 calculation (LWANNIER90_RUN = .TRUE. in the INCAR file), things start getting tricky.

In comparison to non-SOC calculations I just double the number of wannier functions (nuw_wann). But then my calculation does not stop properly and I do not get any output file (despite setting write_hr = T).

In my wannier90.win file I choose num_wann = 16 and spinors = .true. with the following projections on orbital basis functions:

Begin Projections

Hg : sp3

Te : sp3

End Projections.

But then in my log file I get a mysterious message:

.

.

.

Projection 26 done.

Projection 27 done.

Projection 28 done.

Projection 29 done.

Projection 30 done.

Projection 31 done.

Projection 32 done.

MLWF_WANNIER90: ERROR: number of projections not equal to num_wann 32

16

I do not understand why the projections go higher than 16 or the meaning of the error message.

Does anyone of you have experience in including spin orbit coupling in a VASP+WANNIER90 calculation and can explain me what I am doing wrong?

Thank you very much in advance!

Best regards

I have a question concerning the combination of VASP and WANNIER90.

My aim is to calculate Hamiltonian Matrix elements in the Wannier function basis for different materials with spin orbit coupling.

As an example let's take mercury telluride (HgTe).

The vasp calculations work fine, but when it comes to the Wannier90 calculation (LWANNIER90_RUN = .TRUE. in the INCAR file), things start getting tricky.

In comparison to non-SOC calculations I just double the number of wannier functions (nuw_wann). But then my calculation does not stop properly and I do not get any output file (despite setting write_hr = T).

In my wannier90.win file I choose num_wann = 16 and spinors = .true. with the following projections on orbital basis functions:

Begin Projections

Hg : sp3

Te : sp3

End Projections.

But then in my log file I get a mysterious message:

.

.

.

Projection 26 done.

Projection 27 done.

Projection 28 done.

Projection 29 done.

Projection 30 done.

Projection 31 done.

Projection 32 done.

MLWF_WANNIER90: ERROR: number of projections not equal to num_wann 32

16

I do not understand why the projections go higher than 16 or the meaning of the error message.

Does anyone of you have experience in including spin orbit coupling in a VASP+WANNIER90 calculation and can explain me what I am doing wrong?

Thank you very much in advance!

Best regards