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Dear exciting team,

Could you help me with one question? Are the eigenvalues in Exciting given with respect to the average electrostatic potential of the unit cell (as in VASP for example)? For instance if you want to calculate the work function, do you need to build a slab with vacuum and find the average electrostatic potential in vacuum? Thank you for the help! Sorry if that's not a question for support, not sure where to write to…

Eigenvalues are given referenced to? by Alena Vishina (guest), 09 Jul 2018 16:29

I am trying to plot PBE0 KS states using plot3d, but when I use a k point grid that is not 111 or 211, I get this error. This doesn't happen for LDA functionals.

Error(getevecfv): differing vectors for k-point by Luning Zhao (guest), 05 Jul 2018 00:07

Hello,

I was trying to test HF calculations for bulk system. I used the simple example in the tutorial (the carbon one). I think in exciting, HF calculations need a initial DFT calculation, so I calculated PBE first and then replace the PBE tag by HF tag. But the calculated eigenvalues seem to be wrong because the degeneracy is broken. And also it generates a "WARNINGS.OUT", where the charge is wrong. Is there any special settings for HF calculations to prevent such situation? Thanks!

HF calculations by mcjinyemcjinye, 04 Jul 2018 18:08

Dear Hwanhui,

it is difficult to help you understanding why your job is killed with the little information you provide us. How large is your system in terms of atoms and unit-cell size? What parameters are you using in your input file? Can you post your input file?

To have some general indications about how to run XAS calculations with exciting, you may have a look at the corresponding tutorial: http://exciting-code.org/carbon-x-ray-absorption-spectra-using-bse.

Best regards,
Caterina Cocchi
(exciting team)

Dmitrii (guest) 27 Jun 2018 11:10
in discussion Forum / Support Questions » Second harmonic generation

Hi,

You can simulate the temperature-dependent SHG as far as you know the lattice structure for those temperatures (which is probably available from experiment).

Best,
Dmitrii
(the exciting developer team)

by Dmitrii (guest), 27 Jun 2018 11:10
Second harmonic generation
pengfei (guest) 27 Jun 2018 10:54
in discussion Forum / Support Questions » Second harmonic generation

Can Exciting be used to calculate Second harmonic generation at different temperatures´╝č

Second harmonic generation by pengfei (guest), 27 Jun 2018 10:54

Can you please suggest a way to resolve the elastic constants of rhombohedral, monoclinic and triclinic elastic constants using exciting-elastic code? I was looking at the third order elastic constants of few of these systems. Please suggest

Hello,

First, I'm a beginner in EXCITING and DFT, so please excuse my possibly very basic questions.

I've been trying to simulate XAS of BaSnO3 (perovskite crystal).
I'm running EXCITING in a Linux system in university supercomputer.

When I run EXCITING with input.xml (containing <xs> element,) jobs are killed… It generates 'WARNINGS.OUT' output saying 'warning(gndstate): Reached self-consistent loops maximum'

I've been changing parameters in input.xml file, but it has not been successful.
Could I know what parameters or steps I should look up to perform the XAS simulation using EXCITING?

Later, I'll try XAS calculations for a very big supercell (around 100 atoms in a supercell). Would EXCITING code work for the calculation as well?
If it would, is there anything that I should be cautious for a successful simulation?

Also, could I please get some advice on XAS simulation?
(Recommendations on studying materials, online tutorials, etc. would be very welcomed!!)

Many thanks for taking time to read the questions!

Best,
Hwanhui

XAS calculation job killed by Hwanhui YunHwanhui Yun, 18 Jun 2018 18:52

Dear Caterina,
You told Robert to compile the code in parallel (a strong parallelization of the code will make those calculations more affordable). What do you mean by "a strong parallelization of the code"? . I compile the code In the form of mpi, and when I use the command "time excitingmpi", I do not get involved with all my cores. Because my structure has too many atomic numbers, my time calculations are too long. Can you guide me to find my mistake? I want the system to use all the cores for its calculations.
thanks you,
Sahel loushab

Dear Caterina,
You told Robert to compile the code in parallel (a strong parallelization of the code will make those calculations more affordable). What do you mean by "a strong parallelization of the code"? . I compile the code In the form of mpi, and when I use the command "time excitingmpi", I do not get involved with all my cores. Because my structure has too many atomic numbers, my time calculations are too long. Can you guide me to find my mistake? I want the system to use all the cores for its calculations.
thanks you,
Sahel

by Sahel (guest), 09 Jun 2018 06:24

Dear AllFirst I excuse discuss it here,I have problem in making ZrS2 nanotube input file in ASE. When i run my result not trueI write my input file here , please help me about it

nanotube
from ase import *
from math import *

a= 3.772
c= 6.125
atoms = Atoms([Atom('Zr', (0, 0, 0)),
Atom('S', (1/3.,2/3.,0.26)),
Atom('S', (2/3.,1/3.,-0.26))])

cell = [(a,0,0),
(a/2,a*sqrt(3)/2,0),
(0,0,c)]
atoms.set_cell(cell,scale_atoms=True)

from ase.structure import nanotube
zrs2 = nanotube(6,6,8)
zrs2.numbers[::2] = 40
zrs2.numbers[1::2] = 16
zrs2.numbers[1::2]= 16
from ase.visualize import view
view(zrs2)

Thanks

Nanotube input file in ASE by A-hajimalekA-hajimalek, 08 Jun 2018 11:51

Dear All
First I excuse discuss it here,
I have problem in making ZrS2 nanotube input file in ASE. When i run my result not true
I write my input file here , please help me about it

  1. nanotube

from ase import *
from math import *

a= 3.772
c= 6.125
atoms = Atoms([Atom('Zr', (0, 0, 0)),
Atom('S', (1/3.,2/3.,0.26)),
Atom('S', (2/3.,1/3.,-0.26))])

cell = [(a,0,0),
(a/2,a*sqrt(3)/2,0),
(0,0,c)]
atoms.set_cell(cell,scale_atoms=True)

from ase.structure import nanotube
zrs2 = nanotube(6,6,8)
zrs2.numbers[::2] = 40
zrs2.numbers[1::2] = 16
zrs2.numbers[1::2]= 16
from ase.visualize import view
view(zrs2)

Thanks

Dear Caterina,
Can we find the number of symmetries in exciting? how?
Thank you,
Sahel loushab.

Number of symmetries by sahel loushabsahel loushab, 08 Jun 2018 05:33

Dear Caterina.
In the following the first post,i find 3 modmain in "src" file.
1.exciting/src/modmain.f90
2.exciting/src/eos/modmain.f90
3.exciting/src/spacegroup/modmain.f90
In relation to the error mentioned, which of these should be edited? and how?
Beast regards,
Sahel loushab.

Re: modmain.f90 by sahel loushabsahel loushab, 04 Jun 2018 06:57

Dear Caterina,
I'm making a Super cell of phosphoren, each unit cell having four atoms. As long as I put 16 cells together, I have no problem.But when I put 25 cells together, I am getting this error message: Error (findsymcrys): too many symmetries
Adjust maxsymcrys in modmain and recompile code.
can you tell me: where is "modmain" and how can i edite it?
Beast regards,
Sahel loshab.

modmaine.f90 by sahel loushabsahel loushab, 03 Jun 2018 13:12

Dear all,

I am new to the exciting code and trying to learn the basics. So here is the problem:
spin-polarized calculation failed for one H atom.

Non-spin-polarized runs fine:
<input>
<title>H</title>
<structure speciespath="$EXCITINGROOT/species">
<crystal scale="10">
<basevect> 0.5 0.5 -0.5</basevect>
<basevect> 0.5 -0.5 0.5</basevect>
<basevect>-0.5 0.5 0.5</basevect>
</crystal>
<species speciesfile="H.xml" rmt="1.5">
<atom coord="0.0 0.0 0.0"/>
</species>
</structure>

<groundstate
do="fromscratch"
xctype="GGA_PBE"
ngridk="1 1 1"
swidth="0.0001"
epsengy="1.0d-8"
nempty="10">
</groundstate>
</input>

However, if I run with spin-polarization:

<spin
bfieldc="0.0 0.0 -4.0"
reducebf="0.5"
spinorb="false">
</spin>

then the codes does not converge at all
$cat TOTENERGY.OUT
-0.527968258544
-0.501036528507
-0.476198317455
-0.340910415340
-0.230079452411
-0.278306530030
-0.316818033772
-0.285982520306

The moment fluctuates a lot
$grep 'total moment in' INFO.OUT
total moment in muffin-tins : 0.47262656
total moment in muffin-tins : 0.45443637
total moment in muffin-tins : 0.43575175
total moment in muffin-tins : 0.38864728
total moment in muffin-tins : 0.18933229
total moment in muffin-tins : 0.28804897
total moment in muffin-tins : 0.28381672
total moment in muffin-tins : 0.27910153
total moment in muffin-tins : 0.28000629
total moment in muffin-tins : 0.08717027
total moment in muffin-tins : 0.28580776
total moment in muffin-tins : 0.28618238
total moment in muffin-tins : 0.41926533
total moment in muffin-tins : 0.30616399
total moment in muffin-tins : 0.30817578
total moment in muffin-tins : 0.28188012
total moment in muffin-tins : 0.30400412
total moment in muffin-tins : -0.26481978
total moment in muffin-tins : 0.29028972
total moment in muffin-tins : -0.15703249
total moment in muffin-tins : 0.29149950
total moment in muffin-tins : 0.27257125

and XC energy fluctuates between 0 and finite values

$grep 'Exchange\|Correlation' INFO.OUT
Exchange-correlation type : 20
Exchange energy : 0.00000000
Correlation energy : 0.00000000
Exchange energy : 0.00000000
Correlation energy : 0.00000000
Exchange energy : 0.00000000
Correlation energy : 0.00000000
Exchange energy : 0.00000000
Correlation energy : 0.00000000
Exchange energy : 0.00000000
Correlation energy : 0.00000000
Exchange energy : 0.00000000
Correlation energy : 0.00000000
Exchange energy : -0.18163847
Correlation energy : -0.00706027
Exchange energy : -0.18006859
Correlation energy : -0.00722284

I tried linear mixer with small beta0 from 0.2 to 0.05 but it does not help.

In particular I do not understand why most times the XC energy is 0.

Thanks and appreciate your help
Fei

Convergence issue of spin-polarized hydrogen atom by Fei Zhou (guest), 30 May 2018 18:38
Re: MPI run
sahel loushabsahel loushab 30 May 2018 04:10
in discussion Forum / Support Questions » MPI run

Thank you very much dear Caterina.
Beast regards,

Re: MPI run by sahel loushabsahel loushab, 30 May 2018 04:10
Re: MPI run
Caterina CocchiCaterina Cocchi 29 May 2018 19:28
in discussion Forum / Support Questions » MPI run

Dear Sahel Loushab,

with the little information provided, it is evident that the system under study is too demanding for your machine. The exciting code is perfectly suitable for the purpose.

Best regards,
Caterina Cocchi
(exciting team)

Re: MPI run by Caterina CocchiCaterina Cocchi, 29 May 2018 19:28
Re: MPI run
sahel loushabsahel loushab 29 May 2018 17:02
in discussion Forum / Support Questions » MPI run

Dear Cateriena,
I made a Phosphoren Super cell that has 100 atoms.the details of my system :Xeon with 40 core and 62GB memory addition 62GB swap memory.
I will wish to calculate Electronic-structure and LayerOptics. But when I want to do my calculations, I encounter this error message:
forrtl: server (41):insufficent virtual memory
I wanted to know if my system was not suitable for this structure or that the exiting code was not suitable for my project?!
Beast regards ,
Sahel loushab.

Re: MPI run by sahel loushabsahel loushab, 29 May 2018 17:02
Dr. D. P. Rai (guest) 25 May 2018 16:40
in discussion Forum / Support Questions » Elastic with quantum espresso

Hello All

I need help in calculating Elastic constants.
Interfacing QE with Elastic code.

Thanks !

Best Regards

D. P. Rai
Ast. Prof.
PUC, India

by Dr. D. P. Rai (guest), 25 May 2018 16:40
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