Hello,
I was running G0W0+BSE in case of wz-ZnO, when i looked into the output file GW_INFO.OUT, i found this error " WARNING(calcevalqp):Suspicious Znk irk= 1 ie= 92 enk= 2.582 eV Znk= 1.00 ReSc= -0.197 ImSc= -0.116 ReSc'= 0.001 ImSc'= -0.134" for set of k-points.

<input>
<title>ZnO wz</title>
<structure speciespath="/home/mhegde/exciting/species/" tshift="false">
<crystal scale="1.88973">
<basevect>3.174949863 0.000000000 0.000000000</basevect>
<basevect>-1.587474931 2.749587237 0.000000000</basevect>
<basevect>0.000000000 0.000000000 5.119620803</basevect>
</crystal>
<species speciesfile="Zn.xml" rmt="1.8">
<atom coord="0.666666687 0.3333333343 -0.001530974"/>
<atom coord="0.333333313 0.6666666627 0.498469026"/>
</species>
<species speciesfile="O.xml" rmt="1.8">
<atom coord="0.666666687 0.3333333343 0.619530945"/>
<atom coord="0.333333313 0.6666666627 0.119530945"/>
</species>
</structure>

<groundstate
rgkmax="8.0"
ngridk="4 4 4"
gmaxvr="14"
xctype="LDA_PW">
</groundstate>

<gw

taskname="g0w0"
ngridq="4 4 4"
nempty="300"
ibgw="10"
nbgw="150">
</gw>

xstype="BSE"
ngridk="4 4 4"
vkloff="0.097 0.273 0.493"
ngridq="4 4 4"
nempty="100"
gqmax="3.0"
broad="0.007"
scissor="0"
tevout="true">

<energywindow
intv="0.0 1.0"
points="2000"/>

<screening
screentype="full"
nempty="80"/>
<BSE
bsetype="singlet"
nstlbse="1 25 1 100" />

<qpointset>
<qpoint>0.0 0.0 0.0</qpoint>
</qpointset>

</xs>

</input>
is it due to the "screentype" and few number of nempty?. Is it necessary to use the option "vkoff"?. What is the significance of it?l If I am not wrong, it is possible to estimate the binding energy of exciton from the output, right?

Thanks for your feedback.
Manu
(SFU)