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Plugin Development / Bondhistogram plugin
« on: November 4, 2025, 20:47 »
A BondHistogram plugin I made. Currently tested and works for X-2025.06 but should also be fine for slightly older versions.
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General Questions and Answers / Re: Unexpected Transmission Channel in Monolayer Graphene DFT Transport CalculationD
« on: November 4, 2025, 20:44 »
You may need to go up to 100-300 k-points in the periodic direction to resolve artefacts related to the very specific band structure of graphene.
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General Questions and Answers / Re: Whenever trying to open Current density .hdf5 file after execution isnot opening
« on: November 4, 2025, 20:42 »
You don't open the file itself, you select it in the Data View in NanoLab and then you can access the individual objects inside the file. For more assistance, you need to be more specific what exactly you do, with screenshots ideally.
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General Questions and Answers / Re: Connection to Cluster
« on: November 4, 2025, 20:41 »
I think the warning message is quite clear, check your script for absolute paths to files that may not be available on the cluster in the same location. In general, always use relative paths to reference files you need from within a script that gets submitted to a different machine.
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Future Releases / Re: Machine Learning potential that can also predict density of state
« on: November 4, 2025, 20:39 »
I have yet to see a predefined ML model (we should not call them potentials) that can accurately predict DOS across many applications, but training a specific one for a given problem space is something we are working on.
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General Questions and Answers / Re: DFT Phonon Transmission
« on: November 4, 2025, 01:16 »
No, does not sound normal, I'd expect the whole thing to take a few minutes only, even on CPU. OK maybe an hour on CPU, as MACE is slow on CPU.
Maybe do a simple test calculation first on CPU for MoS2 with a similar number of atoms (make some distortion in the center to make it interesting) using the built-in ReaxFF potential in QuantumATK, just to get a feeling for the calculation time.
Maybe do a simple test calculation first on CPU for MoS2 with a similar number of atoms (make some distortion in the center to make it interesting) using the built-in ReaxFF potential in QuantumATK, just to get a feeling for the calculation time.
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General Questions and Answers / Re: Recommended approach to generate an interface between two amorphous materials
« on: October 4, 2025, 01:35 »
Correct, the Builder tools are for crystalline, well-behaved cases where the coincident lattice model makes sense.
There is not really a simple algorithm to create an interface between two random materials. At heart it's a global optimization problem, hard in itself, and any starting point (the configurations you happen to have of the left and right material, respectively) it's just a representative case, and can never be said to be universal, since each time you generate the amorphous sample you will get a new random configuration, and how you choose the surface termination is equally random.
Now, that may have been obvious to you already, but I just wanted to ensure we share the same picture.
As for the approaches you mention, I would definitely try the universal NN-based potentials for this case. They may not be perfect, and often not accurate enough for a reaction barrier or other very detailed calculations, but the time you save from not having to create a new MTP from scratch or even a fine-tuned MACE demo model from compensates for this. And, you can (and probably should) always do a final DFT relaxation - that is, the MLP-generated structure should just be seen as a starting guess for the interface configuration. And, thanks to their speed and readiness, you can try generate dozens or hundred of candidates in very short time.
There is not really a simple algorithm to create an interface between two random materials. At heart it's a global optimization problem, hard in itself, and any starting point (the configurations you happen to have of the left and right material, respectively) it's just a representative case, and can never be said to be universal, since each time you generate the amorphous sample you will get a new random configuration, and how you choose the surface termination is equally random.
Now, that may have been obvious to you already, but I just wanted to ensure we share the same picture.
As for the approaches you mention, I would definitely try the universal NN-based potentials for this case. They may not be perfect, and often not accurate enough for a reaction barrier or other very detailed calculations, but the time you save from not having to create a new MTP from scratch or even a fine-tuned MACE demo model from compensates for this. And, you can (and probably should) always do a final DFT relaxation - that is, the MLP-generated structure should just be seen as a starting guess for the interface configuration. And, thanks to their speed and readiness, you can try generate dozens or hundred of candidates in very short time.
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General Questions and Answers / Re: HartreeDifferencePotential caculation 2
« on: September 24, 2025, 00:21 »
This is a perfectly normal graph. Those "fluctuations" are the actual variations of the potential with atomic resolution.
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General Questions and Answers / Re: Recommended Guideline for Creating a Ternary MTP by Combining Binary MTP
« on: September 24, 2025, 00:19 »
Quick check, do you really need Ge-Se-Te or Ge-Sn-Te (commonly, GST)? If it's the latter, we already have such a potential provided in the package.
Otherwise, you are in for a ride, but a potentially very rewarding one!
Your methodology is sort of correct, but you don't fit separately for 1-3, you combine those steps into one. That is, you include a bunch of basic crystal structures for all combinations in one training set (which you can test against the crystal experimental data). Then, instead of your step 4, you use active learning on a set of random alloys (and/or amorphous structures) of Ge-Se-Te to refine the potential for the full system. Ideally, for different stoichiometries! This is similar to the workflow we used for TiSi2 in the tutorial below, just a bit more complex for your case since you have 3 elements.
https://docs.quantumatk.com/tutorials/mtp-training-c-am-TiSi/mtp-training-c-am-TiSi.html
Otherwise, you are in for a ride, but a potentially very rewarding one!
Your methodology is sort of correct, but you don't fit separately for 1-3, you combine those steps into one. That is, you include a bunch of basic crystal structures for all combinations in one training set (which you can test against the crystal experimental data). Then, instead of your step 4, you use active learning on a set of random alloys (and/or amorphous structures) of Ge-Se-Te to refine the potential for the full system. Ideally, for different stoichiometries! This is similar to the workflow we used for TiSi2 in the tutorial below, just a bit more complex for your case since you have 3 elements.
https://docs.quantumatk.com/tutorials/mtp-training-c-am-TiSi/mtp-training-c-am-TiSi.html
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News and Announcements / Bugfix update QuantumATK X-2025.06-SP1
« on: September 13, 2025, 00:58 »
A small bugfix update QuantumATK X-2025.06-SP1 has been released.
Download the installers from SolvNetPlus as usual.
Fixed issues:
Download the installers from SolvNetPlus as usual.
Fixed issues:
- In rare cases, it was not be possible to create a project folder on some network drives on Windows
- The Jobs tool did not retain user preferences for script auto-start behavior and resets to default.
- In the Editor, using “Find” and “Replace all” to replace a word with itself caused NanoLab to freeze.
- QuantumATK X-2025.06 installation failed on ARM64 Windows machines with x86_64 binary support.
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Scripts, Tutorials and Applications / Re: ModuleNotFoundError for analysis modules (e.g., Analyser, ATK) in version X-2025
« on: September 13, 2025, 00:52 »
Where are these OrientationFunction and NematicOrderParameter functionalities supposed to come from? QuantumATK does not have those functionalities built in. You may have a separate script Analuyser.py which implements them, in which case you try
but that script then needs to be in the same directory as where you run.
Code
from .Analyser import *12
General Questions and Answers / Re: how to restart Defect MTP Training after interruption
« on: September 3, 2025, 03:18 »
In the normal case, the MTP training scripts are fully restartable. So just run it again in the same directory and it will pick up where it left off. But there are many details, so perhaps it doesn't always work...
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Scripts, Tutorials and Applications / Re: How to Apply Heat Flux in NEMD Simulations Using the "Exchange Interval" Option
« on: September 3, 2025, 03:14 »
The heat sinks need to be a bit bigger than just a few atoms, usually 4-5 layers is probably fine.
The other fundamental questions should be answered in the references under https://docs.quantumatk.com/manual/Types/NonEquilibriumMomentumExchange/NonEquilibriumMomentumExchange.html
The other fundamental questions should be answered in the references under https://docs.quantumatk.com/manual/Types/NonEquilibriumMomentumExchange/NonEquilibriumMomentumExchange.html
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General Questions and Answers / Re: CALCULATED CARRIER CONCENTRATION
« on: September 3, 2025, 03:11 »
Use density_of_states.calculateCarrierConcentration(...)
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General Questions and Answers / Re: Analyzing spin-resolved currents across different versions of QuantumATK
« on: September 3, 2025, 03:10 »
Frank, I missed this while on vacation. 2022 files should be fully compatible. It should be very easy to solve with a few lines of Python code, but would need a few more details, like if this is an IVCharacteristics object, or noncollinear calculations, etc. We can handle it over emails.