How DOS is calculated.

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yilmaz · #1 Post by **yilmaz** » Mon Dec 04, 2006 10:24 pm

i have two questions related to DOS

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

n(εi)=[N(εi) - N(εi-1)] ∆ε

∆ε is the distance between two pins

1) does pin mean energy eigenvalues calculated by VASP. How it is determined?.

2) How realistic are the energy level of defects appearing in the DOS plot of semiconductor band gap, calculated by DFT.

thanks alot

#2 Post by **admin** » Tue Dec 05, 2006 2:14 pm

1) no, they are the energy values for which the DOS is evaluated, calculated from (EMIN - EMAX) / NEDOS
2) please mind that DFT is a pure ground state theory in principle, therefore the widths of the main gaps in semiconductors and insulators is not calculated very reliably.