Yambo Community Forum

yambo -i -V RL, a WARNING occured:

<---> [01] Files & I/O Directories
<---> [02] CORE Variables Setup
<---> [02.01] Unit cells
<---> [02.02] Symmetries
<---> [02.03] RL shells
<---> Shells finder |####################| [100%] --(E) --(X)
<---> [02.04] K-grid lattice
<---> [WARNING]Impossible to define the grid unit vectors
<---> [WARNING]Trying to expand the k-grid
<---> [02.05] Energies [ev] & Occupations
<---> [WARNING]Metallic system
<---> [03] Transferred momenta grid
<---> [WARNING][RL indx] 2 equivalent points in the rlu grid found
<---> [RL indx] X grid is not uniform. Gamma point only.
<---> [04] Game Over & Game summary

after initial step, I do the GW calculation by " yambo -p p -g n", the generated yambo.in is as followed:

ppa # [R Xp] Plasmon Pole Approximation
gw0 # [R GW] GoWo Quasiparticle energy levels
HF_and_locXC # [R XX] Hartree-Fock Self-energy and Vxc
em1d # [R Xd] Dynamical Inverse Dielectric Matrix
EXXRLvcs= 3441 RL # [XX] Exchange RL components
Chimod= "Hartree" # [X] IP/Hartree/ALDA/LRC/BSfxc
% QpntsRXp
1 | 1 | # [Xp] Transferred momenta
%
% BndsRnXp
1 | 50 | # [Xp] Polarization function bands
%
NGsBlkXp= 101 RL # [Xp] Response block size
% LongDrXp
1.000000 | 0.000000 | 0.000000 | # [Xp] [cc] Electric Field
%
PPAPntXp= 27.21138 eV # [Xp] PPA imaginary energy
% GbndRnge
1 | 50 | # [GW] G[W] bands range
%
GDamping= 0.10000 eV # [GW] G[W] damping
dScStep= 0.10000 eV # [GW] Energy step to evalute Z factors
DysSolver= "n" # [GW] Dyson Equation solver (`n`,`s`,`g`)
%QPkrange # [GW] QP generalized Kpoint/Band indices
1| 31| 1| 50|
%
%QPerange # [GW] QP generalized Kpoint/Energy indices
1| 31| 0.0|-1.0|
%
~

It is very strange that only one q point in the screening generating automatically ? why for this? You have said that I need to integrate the Bz, how to do it manually?

When I run this GW calculation with the above yambo.in, many errs occured as followed:

[ai2:21097] Signal: Segmentation fault (11)
[ai2:21097] Signal code: Address not mapped (1)
[ai2:21097] Failing at address: 0x4
[ai2:21098] *** Process received signal ***
[ai2:21098] Signal: Segmentation fault (11)
[ai2:21098] Signal code: Address not mapped (1)
[ai2:21098] Failing at address: 0x4
[ai2:21099] *** Process received signal ***
[ai2:21099] Signal: Segmentation fault (11)
[ai2:21099] Signal code: Address not mapped (1)
[ai2:21099] Failing at address: 0x4
[ai2:21100] *** Process received signal ***
[ai2:21100] Signal: Segmentation fault (11)
[ai2:21100] Signal code: Address not mapped (1)
[ai2:21100] Failing at address: 0x4
[ai2:21086] *** Process received signal ***
[ai2:21086] Signal: Segmentation fault (11)
[ai2:21086] Signal code: Address not mapped (1)
[ai2:21086] Failing at address: 0x4
[ai2:21088] *** Process received signal ***
[ai2:21088] Signal: Segmentation fault (11)
[ai2:21088] Signal code: Address not mapped (1)
[ai2:21088] Failing at address: 0x4
...........

The input and pseu files in pwscf calculation are enclosed in the attchment. Could you help me to resolve these ticklish questions?

In addition, the result of pwscf show this sysem is metal, while the one of vasp's calculation show it is semiconducting, why?

in the r_step, it showed:

[03] Transferred momenta grid
=============================


[WARNING][RL indx] 2 equivalent points in the rlu grid found

[RL indx] X grid is not uniform. Gamma point only.
[WR./SAVE//ndb.kindx]---------------------------------------
Polarization last K : 74
QP states : 1 74
X grid is uniform :no
BS scattering :no
- S/N 001790 --------------------------- v.03.04.00 r.2132 -

Dear Zhou,
why did you start another thread? the forum is meant also to be browsed from all users in order to find solutions to common problems, in this way answers to questions are scattered and less easy to find.
A problem similar to the yours was posted here.
There are problems with the K-point sampling:
Yambo works with uniform grids:
1) Use an automatic generated k-point sampling (as in the file "in" and not in-nscf.in)
2) add the flag force_symmorphic=.true. to the system section because Yambo doesn't support non-symmorphic symmetries

n addition, the result of pwscf show this sysem is metal, while the one of vasp's calculation show it is semiconducting, why?

I can't see the output, but probably this system has a quite small gap and you are using a quite huge semaring. Try to eliminate the smearing or reduce the degauss value.

Best,
Daniele

I'm so sorry about that! I will pay an attention.

1) Use an automatic generated k-point sampling (as in the file "in" and not in-nscf.in)
2) add the flag force_symmorphic=.true. to the system section because Yambo doesn't support non-symmorphic symmetries

I redid this calculation according to your sugeestion, However,such errs still exists, namely,

1) in the initial step, it showed:

__ __ ____ ___ ___ ____ ___
| | |/ | | | \ / \
| | | o | _ _ | o ) |
| ~ | | \_/ | | O |
|___, | _ | | | O | |
| | | | | | | |
|____/|__|__|___|___|_____|\___/

<---> [01] Files & I/O Directories
<---> [02] CORE Variables Setup
<---> [02.01] Unit cells
<---> [02.02] Symmetries
<---> [02.03] RL shells
<---> [02.04] K-grid lattice
<---> [WARNING]Impossible to define the grid unit vectors
<---> [WARNING]Trying to expand the k-grid
<---> [02.05] Energies [ev] & Occupations
<---> [WARNING]Metallic system
<---> [03] Transferred momenta grid
<---> [04] Game Over & Game summary

while, in the r_step, the above warning still also occured?

2) only one q point in the screening generating automatically ?

% QpntsRXp
1 | 1 | # [Xp] Transferred momenta
%

Dear Zhou,
in order to receive help, please post:
your qe input, qe output, r_setup, l_setup

Best,

Daniele

Dear Daniele:
please see my input and output files for qe and yambo_step and GW.
note that: in the initial calculation, I can only get r_step and can not get l_step.

Dear Zhou,
looking at your nscf input:
1) Your k-point grid is not set as automatic.
2) Your degauss is as big as before.

Best,

Daniele

Dear Daniele:
　　　　
　　　I regretted that these errors still existed after redoing these calculation as you told me. Is it system-dependent? Because, such calculations on other system, metal or semiconducting, are ok.

Dear Zhou,
sorry but I do not understand your question about system-dependency. I just wrote you that your nscf input file is not correct. Try to check carefully your input files, especially k-point grids (that has to be set automatic) and smearing and redo the calculation from scratch.
Best,
Daniele

Dear Daniele:

I just wrote you that your nscf input file is not correct. Try to check carefully your input files, especially k-point grids (that has to be set automatic) and smearing and redo the calculation from scratch.

I have revised these parameters in my new calculations, however, thses previous errors still existed. If you have time, could you do my calculation in your computer and find the reason? Thank you in advance!

these new input and output files are enclosed in ths attchments