ypp and GW correction

[enorouzi]

Dear All

Dr. Daniele thank you for your helpful reply.

I have problems again.

I use the below command to plot absorption spectra & excitonic properties in Tio2
(rutile) unit cell respectively:

yambo -o b -y d -V resp

this command generates the input file like below:

optics # [R OPT] Optics
bse # [R BSK] Bethe Salpeter Equation.
bss # [R BSS] Bethe Salpeter Equation solver
BSresKmod= "xc" # [BSK] Resonant Kernel mode. (`x`;`c`;`d`)
% BSEBands
1 | 30 | # [BSK] Bands range
%
BSENGBlk= 1 RL # [BSK] Screened interaction block size
BSENGexx= 1 RL # [BSK] Exchange components
BSSmod= "d" # [BSS] Solvers `h/d/i/t`
% BEnRange
0.00000 | 10.00000 | eV # [BSS] Energy range
%
% BDmRange
0.10000 | 0.10000 | eV # [BSS] Damping range
%
BEnSteps= 100 # [BSS] Energy steps
% BLongDir
1.000000 | 0.000000 | 0.000000 | # [BSS] [cc] Electric Field
%

as you see the input has the " BSSmod= "d" " line as you mentioned. And it doesn't
have #WRbsWF # [BSS] flag.

Then I have run ypp command as you see:

ypp -e a

which generate this input:

amplitude # [R] Amplitude
excitons # [R] Excitons
States= "1 - 1" # Index of the BS state(s)
Degen_Step= 0.0100 eV # Maximum energy separation of two degenerate state
s

But when I run ypp faced with the following previous error:

<---> [04.04] K-grid lattice
<---> [04.05] Energies [ev] & Occupations
<---> [05] Excitonic Properties

[ERROR] STOP signal received while in :[05] Excitonic Properties
[ERROR]Diago database does not contain excitonic wfs

And the same error when I run ypp -e w appears so I dont have my output xsf file to see the hole position.


Another question:

I do the GW correction with yambo -g n -p p, is this command true for gw correction? if yes, I have number 2.16eV for rutile(tiO2).

When I insert this number with the below flag
% XfnQP_E
2.1600| 1.0000|1.0000#
%
in the yambo input file I don't have any change in the absorption spectra.


Thank you for your help in advance

[Daniele Varsano]

Dear Enorouzi,

Dear All



yambo -o b -y d -V resp

And it doesn't
have #WRbsWF # [BSS] flag.

Which version of Yambo are you using?,

try with typing yambo -o b -y d -V 2
or yambo -o b -y d -V 3

and look if it appears.

Then I have run ypp command as you see:

ypp -e a

which generate this input:

amplitude # [R] Amplitude
excitons # [R] Excitons
States= "1 - 1" # Index of the BS state(s)
Degen_Step= 0.0100 eV # Maximum energy separation of two degenerate state
s

But when I run ypp faced with the following previous error:

<---> [04.04] K-grid lattice
<---> [04.05] Energies [ev] & Occupations
<---> [05] Excitonic Properties

[ERROR] STOP signal received while in :[05] Excitonic Properties
[ERROR]Diago database does not contain excitonic wfs

And the same error when I run ypp -e w appears so I dont have my output xsf file to see the hole position.

Yes the reason is the same as before, you cannot run this runlevel if you dont' have stored the eigenstate,
if you do not succed to produce your input you can just add the line
WRbsWF without "#" in tour input file, but please let us know the version you are using as we can solve the problem

anyway if you want excitonic wfs you have to produce the input
with ypp -e -w


Another question:

I do the GW correction with yambo -g n -p p, is this command true for gw correction?

yes it is, but if you know the correction for some reason why you want to calculate it?
if you want to apply such correction as a scissor operator you have to do it in the BSE
construction and use the variable KfnQP_E, now you are applying a scissor in the reponse
function you use to calculate the screening in RPA.

Hope it helps.

Daniele