I understand I first need a properly converged system - check. Now, I need to calculate a self-consistent charge density (CHGCAR). Later I have to do a calculation with IBRION = -1, NSW =0, need to increase k points, read previous CHGCAR (ICHARG = 11), and turn symmetry off (ISYM = 0). The DOSCAR file from this 2nd calculation will have the required DoS data.
Doubts:
- Step 1 - less k points, symmetry ON. Step 2 - more k points, symmetry OFF, IBRION = -1, NSW = 0, ICHARG = 11
- Step 1 - less k points, symmetry OFF. Step 2 - more k points, symmetry OFF, IBRION = -1, NSW = 0, ICHARG = 11
- Step 1 - less k points, symmetry OFF. Step 2 - more k points, symmetry ON, IBRION = -1, NSW = 0, ICHARG = 11
- Step 1 - more k points, symmetry ON. Step 2 - same number of k points, symmetry OFF, IBRION = -1, NSW = 0, ICHARG = 11
- Step 1 - more k points, symmetry OFF. Step 2 - same number of k points, symmetry OFF, IBRION = -1, NSW = 0, ICHARG = 11
- Step 1 - more k points, symmetry OFF. Step 2 - same number of k points, symmetry ON, IBRION = -1, NSW = 0, ICHARG = 11
You don't have to switch off the symmetry. 1.- Get converged CHGCAR, 2.- Perform a non-selfconsitent calculation with a higher the k-points number, use ICHARG=11, test different values of SIGMA , test NEDOS values (I would suggest 1200), NSW = 0, LORBIT = 11. You can plot the results with P4VASP
Sinhué López I used ISYM=0 because of these pages:
https://cms.mpi.univie.ac.at/vasp-forum/viewtopic.php?f=3&t=306
https://cms.mpi.univie.ac.at/wiki/index.php/LORBIT
For LORBIT=11, they write that you need to make an ISYM=0 calculation.
Additionally to what Lopez has said, the method to determine the partial occupancies for each orbital (ISMEAR parameter) also needs to be set in the DOS calculation:
1- For a semiconductor- Use ISMEAR=-5 in order to get an appropriate band gap;
2- For metals/molecules- ISMEAR=0 is appropriate to get a smooth plot (but sometimes it can loose details or get too broad, that is why is important to increase the k-point set and adjust the sigma parameter).
For more information, I recommend the link below:
http://www.flapw.de/MaX-4.0/documentation/dos/
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