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Hi,
I am doing GW+PAW calculation for Ag, but the quasiparticle corrections of d bands are wrong,
Anybody know if GW+PAW is suitable for noble metal calculations?
Thanks

The following is my input file
#######################################################################################
#gwpara 2
# Definition of parameters for the calculation of the KSS file
nbandkss1 -1 # Number of bands in KSS file (-1 means the maximum possible)
nband1 80 # Number of (occ and empty) bands to be computed
kssform1 3

# Calculation of the screening (epsilon^-1 matrix)
optdriver2 3 # Screening calculation
gwcalctyp 2
getkss2 -1 # Obtain KSS file from previous dataset
nband2 80 # Bands to be used in the screening calculation
ecutwfn2 30
ecuteps2 10
symchi2 1
awtr2 1 # Note : the default awtr 1 is better
nfreqim2 4
nfreqre2 10
freqremax2 1.

# data 3 Parameters for the GW calculation
optdriver3 4
getkss3 1
getscr3 2
nband3 80
ecutsigx3 65
ecutwfn3 30
gwcalctyp3 2 # contour integral
symsigma3 1
nkptgw3 1
kptgw3
0.000000 0.000000 0.000000
# 0.500000 0.500000 0.000000
bdgw3
1 13

# Closure-trick
gwcomp 1 # Switching on the closure trick
gwencomp 2

use_slk 1
# Data common to the three different datasets
#Definition of occupation numbers
occopt 7
tsmear 0.001 #for d band 0.01 should be ok, for Al is 0.04 Ha



# Definition of the unit cell: fcc
acell 3*7.73 # This is equivalent to 10.217 10.217 10.217
rprim 0.0 0.5 0.5 # FCC primitive vectors (to be scaled by acell)
0.5 0.0 0.5
0.5 0.5 0.0

# Definition of the atom types
ntypat 1 # There is only one type of atom
znucl 47 # The keyword "znucl" refers to the atomic number of the
# possible type(s) of atom. The pseudopotential(s)
# mentioned in the "files" file must correspond
# to the type(s) of atom. Here, the only type is Silicon.

# Definition of the atoms
natom 1 # There are two atoms
typat 1 # They both are of type 1, that is, Silicon.
xred # Reduced coordinate of atoms
0.0 0.0 0.0

# Definition of the k-point grid
#nkpt 10
ngkpt 10 10 10
nshiftk 1
shiftk 0. 0. 0.
#nshiftk 4
#shiftk 0.5 0.5 0.5 # These shifts will be the same for all grids
# 0.5 0.0 0.0
# 0.0 0.5 0.0
# 0.0 0.0 0.5
istwfk *1 # This is mandatory in all the GW steps.

# Use only symmorphic operations
#symmorphi 0

# Definition of the planewave basis set (at convergence 16 Rydberg 8 Hartree)
ecut 35.0 # Maximal kinetic energy cut-off, in Hartree
pawecutdg 140.0 # paw ecutoff
pawmixdg 1


# Definition of the SCF procedure
nstep 50 # Maximal number of SCF cycles
toldfe 1.0d-6 # Will stop when this tolerance is achieved on total energy
# precondition the SCF cycle. The model dielectric
# function used as the standard preconditioner
# is described in the "dielng" input variable section.
# Here, we follow the prescription for bulk silicon.

Hello,

You might need to increase the number of bands in the screening and sigma calculation, did you check the convergence against these ? Also the number of frequencies you use might not be enough. That might be why your quasiparticle corrections are wrong. There is also the possibility that one-shot GW is not enough in which case you might need to switch to quasiparticle self-consistent GW but first try to check the number of bands and frequencies.

David