Recent Posts

11

Scripts, Tutorials and Applications / Re: Exporting COSMO solvent surface

« Last post by yuby on August 27, 2026, 17:15 »

Yes. The traceback indicates that the visualization step, rather than necessarily the COSMO calculation itself, which is what is exhausting memory. QuantumATK is trying to construct an intermediate array of roughly 740 GiB.

There may be a way to work around this by accessing the COSMO surface/tessera data directly from the QuantumATK Python API and writing it to a more suitable format, but the exact approach depends on your QuantumATK version and on which COSMO object/calculator produced the surface.

12

Scripts, Tutorials and Applications / Exporting COSMO solvent surface

« Last post by ulrich_poto on August 26, 2026, 11:55 »

Dear QuantumATK community,

I would like to visualize a COSMO solvent surface of a very large system but cannot do so within the GUI:

Traceback (most recent call last):
  File "zipdir/NL/GUI/Tools/Data/DataCatalogWidget.py", line 846, in _onDoubleClicked
  File "zipdir/NL/GUI/Tools/Data/DataCatalogWidget.py", line 947, in open
  File "zipdir/NL/GUI/Tools/Data/ToolAnalysisPlugins.py", line 134, in createWidget
  File "zipdir/NL/GUI/Tools/Viewer/Viewer.py", line 1023, in addObjects
  File "zipdir/NL/GUI/Tools/Viewer/Viewer.py", line 1015, in createAndPopulateScene
  File "zipdir/NL/GUI/Tools/Viewer/Viewer.py", line 413, in _addObjects
  File "zipdir/NL/GUI/Graphics/GL/Scene/Scene.py", line 712, in addCosmoSurface
  File "zipdir/NL/Calculators/DensityFunctionalTheory/LCAOCalculator/SolvationModel/CosmoSolventSurface.py", line 526, in tesseraeChargeDensities
  File "zipdir/NL/CommonConcepts/PhysicalQuantity.py", line 1337, in __sub__
numpy.core._exceptions._ArrayMemoryError: Unable to allocate 740. GiB for an array with shape (918636, 36051, 3) and data type float64

While I am aware how ridiculously large this array is, I was wondering if there was any way how to export it in a (maybe even compressed) format so that it can be visualized using an alternative software? So far, I could not find any export options.

Many thanks in advance!

Kind regards,
Ulrich

13

General Questions and Answers / Different phase colors for different transmission eigenchannels

« Last post by Jahanzaib on August 24, 2026, 14:01 »

I'm plotting transmission eigenchannels in QuantumATK using isosurfaces with the BlueRed colormap, where color shows Phase (radians). When I plot two different eigenchannels at the same energy, they show different color/phase patterns even though they're in the same spot on the molecule. Is this normal, or does it mean something is wrong with my setup? Also, if I just want to compare how "big" or "spread out" the two channels are (not their phase), should I be plotting something else instead, like the magnitude/amplitude?

14

General Questions and Answers / Publication reference for the ML-DFT Density Predictor

« Last post by Lim changmin on August 11, 2026, 07:20 »

Hello,

I am currently using the ML-DFT DensityPredictor introduced in QuantumATK Y-2026.03.

The release notes explain that it uses a graph neural network to predict DFT-quality electron densities and can provide an initial density for SCF calculations. However, I could not find a publication reference describing the underlying methodology.

Is the Density Predictor based on any previously published method or research paper? If so, could you please provide the recommended reference(s)?

I would also like to know what reference would be most appropriate when mentioning the use of the QuantumATK Density Predictor in a research paper.

Thank you.

15

General Questions and Answers / error in running QATK

« Last post by Dr. Sabyasachi Sen on July 25, 2026, 14:29 »

getting the attached error while trying to open QATK

Cannot connect to license server system.
 The license server manager (lmgrd) has not been started yet,
 the wrong port@host or license file is being used, or the
 port or hostname in the license file has been changed.
Feature:       qatk_nanolab
Server name:   172.17.52.59
License path:  [email protected];
FlexNet Licensing error:-15,10032

16

General Questions and Answers / HOMO LUMO

« Last post by Jahanzaib on July 18, 2026, 03:29 »

I have optimized the geometry of an isolated molecular system using DFT-LCAO in QuantumATK. For device calculations, I understand that the Molecular Projected Self-Consistent Hamiltonian (MPSH) is used to obtain the molecular energy levels in the presence of electrodes.

However, for a simple isolated molecule (MoleculeConfiguration) without any electrodes, what is the recommended way to calculate and visualize the HOMO and LUMO in QuantumATK?

17

General Questions and Answers / Mobility workflow completes Electron–Phonon Coupling but no mobility output

« Last post by Nemthianhoi Zou on July 6, 2026, 06:56 »

I am trying to calculate the carrier mobility of K₃BiI₉ using the Mobility (Full) workflow. Although most of the workflow appears to execute successfully, I am unable to obtain the final mobility results and would appreciate your guidance. The following intermediate calculations appear to be completed successfully:

✔ Self-consistent field (SCF)
✔ Band structure
✔ Dynamical Matrix
✔ Hamiltonian Derivatives
✔ Phonon Band Structure
✔ Electron–Phonon Coupling (at least up to lifetime calculation)

The only missing output is the final mobility result.
Is the Mobility (Full) workflow fully supported for Hybrid (HSE) + Noncollinear SOC calculations in QuantumATK X-2025.06?
Could the HDF5 file become corrupted even when the Job Manager reports that the task has finished successfully?
Is there any known issue in QuantumATK X-2025.06 that could prevent the mobility object from being written after the electron–phonon coupling calculation?
Is there any additional debug option or verbose logging that I can enable to determine where the workflow stops after the lifetime calculation?
Would you recommend performing the mobility calculation using PBE/PBE+SOC instead of HSE+SOC, or should the current setup work correctly?

18

General Questions and Answers / G0W0 - k-point related error message

« Last post by hagelberg on June 22, 2026, 15:41 »

Hello -
This is about a G0W0 calculation on a nanoribbon system. The job fails with the error message
"The k-point sampling needs to be a least '5' in each direction for metallic systems, if a Gamma-point correction is used."
Some comments:
(1) Even the minimal choice of 5x5x5 makes my system prohibitively large.
(2) As the system is one-dimensional, it should be possible to select k_x = k_y = 1 for the non-periodic directions.
(3) Since the system is an AFM zigzag nanoribbon, it should be semiconducting (the expected bandgap is around 0.8 eV), and so the metallicity assignment looks like a misdiagnosis.
(4) Setting 'include_gamma_point=False' does not seem to change anything.
My question, therefore: Is there any way around the k-points constraint for G0W0 calculations?

Please find the respective .py input file attached. I'm using QuantumATK-X-2025.6.
Thanks a lot,
Frank Hagelberg

19

General Questions and Answers / Re: Update - Stress outliers in TrainingSet

« Last post by AsifShah on June 16, 2026, 06:50 »

Dear all,

QuantumATK only allows setting the threshold for forces, not energies or stresses.
I have written a code that removes stress outliers from TrainingSet.

Link: https://github.com/AsifShah-19/QuantumATK-Scripts

Thankyou

20

General Questions and Answers / tutorial on using COSMO-RS with version 2024 or 2025

« Last post by KHipps on June 12, 2026, 22:50 »

I am looking for information on how to use Quantum ATK with COSMO-RS to calculate temperature dependent heats of solution.  Are there tutorials anywhere?  Can anyone provide a basic example?