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Dear all,

With the spin-orbit interaction tag LSORBIT = .TRUE., I tried to extract the PARCHG for specific energy state after the band structure calculations.

I set the LPARD = .TRUE., LSEPB= .TRUE. and LSEPK=.TRUE..
Then, I specified the point I want to plot using the IBAND and KPUSE tags as usual.

I got the PARCHG files accordingly, however I found the result in PARCHG is unexpected character since it contains negative values!
I found someone already noticed about this issue and posted in elsewhere http://cms.mpi.univie.ac.at/vasp-forum/ ... CHG#p14909.

I found admin's reply that PARCHG is only available in the non-magnetic runs.

admin wrote:PARCHG is only available for non-magnetic runs

What is that mean? Is it because of the some technical problem (related with the code..) or is there any other physical reason?
And if it is not possible, how can I get PARCHG for specific band in certain k-point?
Is there any other way?

Sincerely,
Kim.

Do not mix the concept of spin polarization (working with spin-up and spin-down quantities)
with the concept of spin orbit coupling. The SOC concept uses 4-component spinors
and spin-up and spin-down quantities are not defined anymore.
Upon swithing on LORBIT = .TRUE. spin-up and spin-down electron densities are not
calculated, therefore PARCHG does not contain relevant numbers.
Actually the combination of tags LORBIT=T and LPARD=T should generate
a warning message.

I did not want to calculation spin up or spin down part of the state.
I just want to get the wave function squared |psi|^2 for certain band and k-point.
I did not said that I want to calculate spin-up and down densities in the SOC calculations.
And I can sure that there was no such WARNING messages you've mentioned.
It is post processing performed after the band structure calculation with generated WAVECAR file.
And I expected that, since there is wave function information for certain state it should be give some relevant outputs.
Version is VASP5.2. Did it improved for latest version?
Am I still confusing SOC method?

Thank you.
Kim.