DOSCAR

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The DOSCAR file contains the DOS and integrated DOS. The units are number of states/eV and number of states, respectively and thus extensively defined. The intensive DOS is obtained by dividing by the Volume of the unit cell. For dynamic simulations and relaxations, an averaged DOS and an averaged integrated DOS is written to the file. For a description of how the averaging is done see the tags NBLOCK, KBLOCK, EMIN, EMAX and NEDOS. The first few lines of the DOSCAR file are made up by a header:

Number of Ions (including empty spheres), Number of Ions, 0 (no partial DOS) or 1 (incl. partial DOS), NCDIJ (currently not used)     
Volume of the unit cell [Angst**3], length of the basis vectors (a,b,c [m]), POTIM[s]
the initial Temperature TEBEG 
'CAR'
the name of the system as given by SYSTEM in INCAR
E(max), E(min), (the energy range in which the DOS is given), NEDOS,  E(fermi), 1.0000
which is followed by NEDOS lines holding three data
energy     DOS     integrated DOS

The density of states (DOS) , is actually determined as the difference of the integrated DOS between two pins, i.e.

where is the distance between two pins (energy difference between two grid point in the DOSCAR file), and is the integrated DOS

This method conserves the total number of electrons exactly. For spin-polarized calculations each line holds five data

energy     DOS(up) DOS(dwn)  integrated DOS(up) integrated DOS(dwn)

If RWIGS or LORBIT (important for Wigner Seitz radii) is set in the INCAR file, an lm- and site-projected DOS isvcalculated and also written to the DOSCAR file. One set of data is written for each ion, each set of data holds NEDOS lines with the following data

l-resolved:

energy s-DOS p-DOS d-DOS,

lm-resolved DOS (l,-m,...,l,0,...l-,+m):

energy, 

for spin-polarized systems [[{{{1}}}]]:

energy s-DOS(up) s-DOS(down) p-DOS(up) p-DOS(dwn) d-DOS(up) d-DOS(dwn)

for the non spin-polarized and spin polarized case respectively. As before the written densities are understood as the difference of the integrated DOS between two pins.

For non-collinear calculations, the total DOS has the following format:

energy     DOS(total)   integrated-DOS(total) 

Information on the individual spin components is available only for the site projected density of states, which has the format:

energy s-DOS(total) s-DOS(mx) s-DOS(my) s-DOS(mz) p-DOS(total) p-DOS(mx) ...

In this case, the (site projected) total density of states (total) and the (site projected) energy resolved magnetization density in the (mx), (my) and (mz) directions are available.

In all cases, the units of the l- and site projected DOS are states/atom/energy.

The site projected DOS is not evaluated in the parallel version for the following cases:

  • vasp.4.5, NPAR1 no site projected DOS
  • vasp.4.6, NPAR1, LORBIT=0-5 no site projected DOS

In vasp.4.6 the site projected DOS can be evaluated for LORBIT=10-12, even if NPAR is not equal 1 (contrary to previous releases).

  • vasp.5 needs no specification of NPAR

Mind: For relaxations, the DOSCAR is usually useless. If you want to get an accurate DOS for the final configuration, first copy CONTCAR to POSCAR and continue with one static (ISTART=1; NSW=0) calculation.


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