I've tried to use I ISMEAR=-5 since my system that is supposed to be semiconductor or insulator.
The result was however, too shape. Even if I increse the mesh for KPOINTS, it still showed the same problem.
Therefore, I used "ISMEAR=0" and KPOINT of 2X3X3 or 3X3X3 (even 6*6*6).
Should it be all right?
If not, what should I do for it? Should I have to use ISMEAR=-5?
What does SIGMA in DOS section mean in detail, and what should I assign for SIGMA in common?
With best regards,
Sincerely
Luke
questions on DOS for semiconductor or insulator
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luke419
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questions on DOS for semiconductor or insulator
Last edited by luke419 on Mon Feb 22, 2010 2:03 am, edited 1 time in total.
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questions on DOS for semiconductor or insulator
the tetrahedra methods do not 'smear' the levels, therefore the DOS can only be smoothened when plotting the curves.
SIGMA is the smearing width of the levels, it depends on your system which value to choose (gap width,...), usually 0.1 is a good choice. please note that systems with no 3D periodicity like molecules or small clusters have discrete levels.
SIGMA is the smearing width of the levels, it depends on your system which value to choose (gap width,...), usually 0.1 is a good choice. please note that systems with no 3D periodicity like molecules or small clusters have discrete levels.
Last edited by admin on Fri Mar 05, 2010 8:47 pm, edited 1 time in total.