[Wannier] wannier WF and Hamiltonian

[Liping Chen]

Dear wannier users,

I want to show the wannier WF with xcrysden. I find that there is an example (the first one) in wannier90 tutorial. It seems that the UNK* files should to be prepared in advance. It's easy to get them by PWSCF. But now I'm using VASP. I've tried to check the WAVECAR from VASP. It seems that the WAVECAR for the coefficients is written like this:
##################################################
do ik=1,num_kpoints
  do iband=1,nband
    do iplane=1,nplane
      coeff(iplane,iband) ! write the coefficients
    enddo
  enddo
enddo
##################################################
The number of plane waves (nplane) is not the same for all the kpoints (ik). I don't know the relationship the number of plane waves and the ngx, ngy, ngz written in the beginning of the UNK* files. How to get the UNK* files from VASP so that I can get the WF from wannier and then plot it?

In the previous discussion of "how to calculate fermi surface with VASP and WANNIER90", it seems that Jonathan said WF should be real. Then should the Hamilton matrix <0n|H|Rm> and the position matrix <0n|r|Rm> in WF basis be real accordingly? But when I print out hamiltonian matrix with "hr_plot = true", it's not real but complex with unignorable imaginary part. Is it wrong or not? 

Thanks in advance!

Liping Chen
Department of Chemistry
University of Rochester