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What does machine learning learn about DFT?

Total energies and HOMO-LUMO gaps are very different quantities, and naturally necessitate very different neural network designs (including the choice of descriptors and architectures) in order to ...
• 7,233
Accepted

Artificial intelligence is a hot topic, but should I pursue it if I'm interested in Matter Modeling?

"I am a student now and should decide my major to research soon. AI/ML is a very hot research field and I am very interested in it, but I have some doubts before I study AI/ML." AI is ...
• 28.8k
Accepted

Is it possible to calculate the pka value of different H atoms on one molecule?

Yes. Simply calculate the pKa from the definition: $$\rm{pK_a} = \lg \frac{[AH]}{[A^-][H^+]} \tag{1}$$ The equilibrium constant in the logarithm is computed from the Gibbs free energy of the ...
• 7,233

What does machine learning learn about DFT?

It could just be that the features you are using are well suited for describing total energies in these sorts of systems, but not in describing the differences of eigenvalues. When people do ML to try ...
• 506

Artificial intelligence is a hot topic, but should I pursue it if I'm interested in Matter Modeling?

I did my master's research project in predicting absorption spectra using machine learning (with fingerprints). So, my research is somewhat in the field of material modelling you can say. I want to ...
• 5,754
Accepted

SOC calculations in VASP

Sometimes the forces will be similar with and without SOC, so you can relax without SOC, and then do a single point calculation on the relaxed structure with SOC. When you do that calculation, you ...
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• 453

3D band structure plot

Usually people just do it by picking a path through the Brillouin zone and then plotting it in one dimension. You can use the seekpath or pymatgen (I think pymatgen has this) tools to generate paths ...
• 506

Create doped structures to POSCAR files for vasp

Cluster Expansion Codes Several codes can help with fitting a cluster expansion (CE) to this problem. A cluster expansion uses (small-cell) computed DFT energies and maps them to short-range multi-...

Issues converging with DFT+U and magnetism in Quantum ESPRESSO

As a solution, you should check if convergence is difficult due to the magnitude of your Ru U correction. Try smaller corrections and see if that helps. You can also try applying a correction to the ...
• 10.1k
1 vote

Why Kohn-Sham equations are regarded as single-particle equations?

I would argue that because the exact potential, like the ground state density, is a property of the system. The Hohenberg-Kohn theorems show that there is a scalar single-particle potential \$v({\bf r})...
• 14.7k
1 vote

What happens to the position coordinates of the nearest neighbors in supercell studies?

In solid-state calculations, DFT code does not know whether you give it a crystalline unit cell or a supercell. Instead, it treats every input structure as a "unit cell". So my answer is &...
• 139

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