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Hallo to everybody.
I'm facing a strange phenomenon. I was trying to compute RPA absorption spectrum using GW energies, so I put OMEGAMAX=20 and NEDOS=2001 in my GW input file (see related topic: 'Physics questions / RPA calculation for GW ' a help also there will be appreciated).
I did not obtain the RPA spectrum but not only that! I did not even obtained the same GW corrections I computed for an exactly equivalent calculation without NEDOS nor OMEGAMAX, although these parameters should not enter in the calculation of sigma.

Here you can find INCAR and part of the OUTCAR from the two calculations:

================================
== calculation with NEDOS and OMEGAMAX ==
================================
INCAR:

NPAR = 16

ALGO = GW0
LSPECTRAL = True
LOPTICS = True
LRPA = True
PRECFOCK = FAST
PREC = High
ENCUT = 704.00 eV

NOMEGA = 100
NBANDS = 560
ENCUTGW = 704.00 eV
CSHIFT = 0.1

NBANDSGW = 48
LMAXFOCKAE = 4
NKRED = 2
ODDONLYGW = True
MAXMEM = 4000

NEDOS = 2001
OMEGAMAX = 20
CSHIFT = 0.1

ISMEAR = 0 ; SIGMA = 0.05

OUTCAR:
k-point 1 : 0.0000 0.0000 0.0000
band No. KS-energies QP-energies sigma(KS) V_xc(KS) V^pw_x(r,r') Z occupation

1 -16.8994 -17.9330 -22.6790 -21.2405 -30.2115 0.7185 2.0000
2 -4.2271 -5.6216 -24.1207 -22.2912 -30.7202 0.7622 2.0000
3 -4.2271 -5.6216 -24.1207 -22.2912 -30.7202 0.7622 2.0000
4 -4.2271 -5.6216 -24.1207 -22.2912 -30.7202 0.7622 2.0000
5 -3.0956 -4.5970 -25.3654 -23.4590 -32.4407 0.7875 2.0000
6 -3.0956 -4.5970 -25.3654 -23.4590 -32.4407 0.7875 2.0000
7 2.4616 1.0541 -23.9387 -22.1911 -27.0544 0.8054 2.0000
8 2.4616 1.0541 -23.9387 -22.1911 -27.0544 0.8054 2.0000
9 2.4616 1.0541 -23.9387 -22.1911 -27.0544 0.8054 2.0000



================================
== calculation without NEDOS and OMEGAMAX ==
================================
INCAR:
NPAR = 16

ALGO = GW0
LSPECTRAL = True
LOPTICS = True
LRPA = True
PRECFOCK = FAST
PREC = High
ENCUT = 704.00 eV

NOMEGA = 100
NBANDS = 560
ENCUTGW = 704.00 eV
CSHIFT = 0.1

NBANDSGW = 48
LMAXFOCKAE = 4
NKRED = 2
ODDONLYGW = True
MAXMEM = 4000

ISMEAR = 0 ; SIGMA = 0.05

OUTCAR:
k-point 1 : 0.0000 0.0000 0.0000
band No. KS-energies QP-energies sigma(KS) V_xc(KS) V^pw_x(r,r') Z occupation

1 -16.8994 -17.3244 -21.8446 -21.2405 -30.2115 0.7036 2.0000
2 -4.2271 -4.9498 -23.2762 -22.2912 -30.7202 0.7337 2.0000
3 -4.2271 -4.9498 -23.2762 -22.2912 -30.7202 0.7337 2.0000
4 -4.2271 -4.9498 -23.2762 -22.2912 -30.7202 0.7337 2.0000
5 -3.0956 -3.8983 -24.5191 -23.4590 -32.4407 0.7571 2.0000
6 -3.0956 -3.8983 -24.5191 -23.4590 -32.4407 0.7571 2.0000
7 2.4616 1.7613 -23.0983 -22.1911 -27.0544 0.7719 2.0000
8 2.4616 1.7613 -23.0983 -22.1911 -27.0544 0.7719 2.0000
9 2.4616 1.7613 -23.0983 -22.1911 -27.0544 0.7719 2.0000




Is this a bug or I am messing up things?
Thanks for any help!
<span class='smallblacktext'>[ Edited ]</span>

Hi,

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