PARCHG - band decomposed charge density (spin dependent)

Queries about input and output files, running specific calculations, etc.


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denis
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PARCHG - band decomposed charge density (spin dependent)

#1 Post by denis » Wed Aug 17, 2005 8:36 pm

If I am calculating band- (and k-) decomposed charge density within certain limits with respect to the Fermi energy, at a single k-point (Gamma), and band number N minority spin is within these limits, but the band number N majority spin is not, will my PARCHG file contain spin-up+spin-down components of charge anyway? Because within those limits it should only contain minority spin charge. But ...

the second set in the PARCHG file ((spin-up)-(spin-down) charge) has both negative and positive values, indicating magnetization density, for a single band.

Any help is greatly appreciated.
Last edited by denis on Wed Aug 17, 2005 8:36 pm, edited 1 time in total.

admin
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PARCHG - band decomposed charge density (spin dependent)

#2 Post by admin » Mon Aug 22, 2005 1:58 pm

yes, the current implementation of the partial band-decomposed charge density adds up the density of the n-th band of up and down spin, irrespective of whether both or just one of the bands are in the specified energy range or not.
Last edited by admin on Mon Aug 22, 2005 1:58 pm, edited 1 time in total.

xinhuanwen

PARCHG - band decomposed charge density (spin dependent)

#3 Post by xinhuanwen » Mon Apr 25, 2011 6:34 am

but if you used the specific bands, the parchg file only contain the spinup component, do not have the spindown . the two components in parchg file was same as each other ,thy are both the spinup component ,why ?
Last edited by xinhuanwen on Mon Apr 25, 2011 6:34 am, edited 1 time in total.

superyoyo
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PARCHG - band decomposed charge density (spin dependent)

#4 Post by superyoyo » Wed Apr 27, 2011 5:48 am

@ xinhuanwen,

You need to get the fixed parsden.F and then recompile VASP. It was a bug.

Cheers!
Last edited by superyoyo on Wed Apr 27, 2011 5:48 am, edited 1 time in total.

bernstei
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PARCHG - band decomposed charge density (spin dependent)

#5 Post by bernstei » Thu Jun 16, 2011 5:37 pm

We're seeing a similar problem (both grids printed out in PARCHG.00NM have the same information for band projected densities), but only for hybrid functionals. For PBE, it seems to behave sensibly (first grid is consistent with total density, and second with magnetization). It seems to be related to the fact that when you're doing a PAW calculation without exact exchange ISYM is set to 2 by default, but for hybrid functionals it's set to 3.

Has anyone else seen this problem? Would an example input showing the issue help?

thanks,
Noam

P.S. I'm using the latest 5.2.11 version from the ftp site (date Jan 18 2011). The web portal version is dated Nov 2010.
Last edited by bernstei on Thu Jun 16, 2011 5:37 pm, edited 1 time in total.

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