Recent Posts

61

General Questions and Answers / Local energy in MTP calculation

« Last post by nils.holle on April 9, 2024, 17:43 »

Hello, in principle, machine-learned potentials can deliver site energies, i.e. the total energy can be written as a sum of atomic energies. Is it also possible using the TremoloX calculator to calculate energies of single atoms in a larger system? Thanks!

62

General Questions and Answers / Re: Phonon dispersion is senstitive to "processes_per_displacement" paramter of DM?

« Last post by krabidix on April 9, 2024, 09:34 »

These are the dynamical matrix files for both cases.
I think this is complete information!

Now, the question can be addressed: why phonon dispersion is senstitive to "processes_per_displacement" paramter?

63

General Questions and Answers / Re: Phonon dispersion is senstitive to "processes_per_displacement" paramter of DM?

« Last post by krabidix on April 9, 2024, 09:29 »

Hi,
These are relevant data of both cases ( with processes = 28 and 4).

64

General Questions and Answers / Re: Bandstructure of B-P nanosheet not calculated correctly

« Last post by sguha on April 9, 2024, 06:33 »

Thank you. After doing DFT, I got closely accurate bandgap of 0.89ev.

65

General Questions and Answers / LDA+U in noncollinear spin

« Last post by Dongzhe on April 8, 2024, 16:53 »

Dear ATK experts,

In QuantumATK-V-2023.12, is it possible to model LDA+U with noncollinear spins?

Thanks,
Best regards,
Dongzhe (CNRS, France)

66

General Questions and Answers / Re: Bandstructure of B-P nanosheet not calculated correctly

« Last post by Anders Blom on April 6, 2024, 20:23 »

The paper you refer to is done with DFT, but your model in the script is using an extended Huckel model. That might work, sometimes, and would save a lot of time, however as your test shows, for this system the Huckel parameters do not give the correct band structure etc for B-P, thus it cannot be used.

You might try other parameters such as the Muller or Hoffmann models, and also it will be important to perform the calculations self-consistently since there will be significant charge transfer between B and P atoms (might try that with Cerda parameters too but I doubt it will work, as the two parameter sets you are trying to mix come from fits to AlP and BN).

I think your main option will be DFT in this case.

67

General Questions and Answers / Re: Add dielectric to the electrode region

« Last post by Anders Blom on April 6, 2024, 00:54 »

Add the dielectric region, going all the way out to the edges of the system in C (Z), before creating the device. Then when you use Device from Bulk, the regions will automatically be copied into the electrodes.

68

Installation and License Questions / Re: Error while opening Quantumatk

« Last post by Anders Blom on April 6, 2024, 00:51 »

Looks like the main.ini file was corrupted, try rename it to main-backup.ini and try again. The file is in C:\Users\username\.quantumatk or .vnl for old versions.

69

General Questions and Answers / Re: Phonon dispersion is senstitive to "processes_per_displacement" paramter of DM?

« Last post by Anders Blom on April 6, 2024, 00:43 »

These are for 28 processes, right? The point will be to compare with the run using 4, so please upload those too.

70

General Questions and Answers / Re: Phonon dispersion is senstitive to "processes_per_displacement" paramter of DM?

« Last post by krabidix on April 2, 2024, 11:09 »

Here are the log files for forces and scf.