Dear All,
I am doing right now some calculations on some interface systems by means of PBE+U. Some of these interfaces have a clear semiconductor character.
Anyway, one of such interface systems still results metallic according to PBE+U results (mind that experimentally the same system should be a zero gap semiconductor).
Once I pass to the calculation of the optical spectrum (epsilon2 at RPA level) by switching LOPTICS=.TRUE. I observe a very intense peak at E close to zero.
At first I was thinking this as consequence of the Drude effect.
But right now I am wondering if Drude term is included in the present implementation of VASP (VASP 5.2.12).
If not, can this peak be associated with a wrong choice of the smearing which in my calculation is set as ISMEAR=-5?
May anyone kindly give me any hint?
Best regards,
Giacomo
Here the INCAR file for optical properties calculation
SYSTEM = Graphene
GGA = PE
ISTART = 1
VOSKOWN = 1
ALGO = Normal
LREAL = .FALSE.
PREC= High
ENCUT=500.
ENAUG=605.
ISMEAR = -5
SIGMA = 0.05
NELMIN = 4
NELM = 200
ISIF = 2
ISPIN = 2
IBRION = 1
EDIFF = 1.E-5
EDIFFG = -0.005 ! inizialmente -0.004
NSW = 0
LORBIT = 12
ICHARG = 11
NEDOS = 2000
NBANDS = 288
LOPTICS=.TRUE.
LDAU=.TRUE.
LDAUTYPE=2
LDAUL=-1 2 1
LDAUU=0.0 4.0 3.5
LDAUJ=0.0 0.0 0.0
Drude term in the calculation of epsilon2
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giacomo giorgi
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Drude term in the calculation of epsilon2
Last edited by giacomo giorgi on Fri Jan 10, 2014 11:30 am, edited 1 time in total.
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support_vasp
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Re: Drude term in the calculation of epsilon2
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