I'm studying nanotubes. I first relax the ions and then run a static (NSW=0, IBRION=-1) selfconsistent calculation with a k-points file that points down the length of the nanotube (quazi 1-dimensional). I grab the DOS from that run and then perform another run with the new CHGCAR file using the value of ICHARG=11, changing the k-points file (still pointing down the tube but with more k-points).
My question is this: Do I need to change anything else in the INCAR file while I run it with ICHARG=11? What values should I have for NSW and IBRION? Are there any other errors in my procedure?
couldn't find anything in the manual. Appreciate the help.
Peter Lyon
Last step in Band Structure Calculation
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Last edited by lyon0100 on Mon Nov 23, 2009 6:30 am, edited 1 time in total.
Last step in Band Structure Calculation
NSW = 0 for ICHARG = 11 -> Non-self-consistent run
IBRION and ISIF can be commented out b/c you are no longer doing a relaxation
IBRION and ISIF can be commented out b/c you are no longer doing a relaxation
Last edited by panda on Tue Nov 24, 2009 11:45 pm, edited 1 time in total.
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for a non-scf run, the geometry should be kept, it makes no sense to 'relax' a structure with a fixed potentials
Last edited by admin on Tue Dec 01, 2009 1:50 pm, edited 1 time in total.
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Last step in Band Structure Calculation
So when I calculate the Band Structure, I should leave IBRION=-1? Is that what you're refering to?
Last edited by lyon0100 on Wed Dec 02, 2009 7:57 pm, edited 1 time in total.
Last step in Band Structure Calculation
I think what he is saying is that when NSW = 0 that no ionic steps are performed, eg the geometry remains fixed so the choice of IBRION/ISIF is irrelevant - you already have your xtal structure from the scf calculation so you then only need to perform the non-scf to get the bands
Last edited by panda on Mon Dec 07, 2009 6:22 pm, edited 1 time in total.