Recent Posts

61

General Questions and Answers / Re: configuration for Training set created by random displacement parameters

« Last post by Anders Blom on October 18, 2024, 20:27 »

The tables are not for visualization, and in fact often do not contain any configurations, only the instructions how to make them. But you should have a file that contains a TrainingSet. If you select this you can see the training configurations in the Preview window on the right. Also, and perhaps better, there should be a file containing either an "mtp" or "mtp_active_learning" object. If you right-click these, they can be opened in the Movie Tool where you can see all configurations.

62

General Questions and Answers / Re: Hall conductivity and Seebeck coefficient

« Last post by Anders Blom on October 18, 2024, 20:19 »

For Seebeck see https://docs.quantumatk.com/tutorials/phonon_calcs/phonon_calcs.html
Hall answered in a separate post

63

General Questions and Answers / Re: Compute Hall coefficient and Hall conductivity tensors

« Last post by Anders Blom on October 18, 2024, 20:18 »

The Hall coefficients can optionally be calculated via the Mobility study object, see https://docs.quantumatk.com/manual/Types/Mobility/Mobility.html. It's turned off by default because it's rather time-consuming.

There is no specific tutorial on it, but fundamentally it's just another output of a mobility study.

64

General Questions and Answers / Re: How to reduce memory usage

« Last post by dmicje12 on October 18, 2024, 06:17 »

229 atoms is not a lot, but when you use MPI parallelization the memory duplication can be quite large. So the main suggestion is to reduce MPI and use more threading.

It works!
Thanks for reply!

65

General Questions and Answers / Re: Grain Boundary Scattering doping problem

« Last post by Anders Blom on October 17, 2024, 08:23 »

The total energy is only used to compute the formation energy of the grain boundary. If you don't need that, you can of course skip it.

Not sure why the Sigma3 gives a finite transmission, but as you noted, it will generally not be the case.

66

Installation and License Questions / Re: Cannot assign more than 5 cores for AKMC

« Last post by Anders Blom on October 17, 2024, 08:17 »

Sorry, my previous post is not entirely correct.

The number of saddle searches is controlled by how many MPI processes you assign, divided by processes_per_saddle_search. But this is only relevant if you want each saddle search to be MPI parallel, and normally we don't need or want that for force fields.

Instead, what you want is to run 6 (see above) MPI processes, i.e. mpiexec -n 6 but ensure that the job has access to all the cores on the machine, so each saddle search can thread over the cores. This is a matter of reserving the relevant number of cores in the job scheduler, if you have one, and you might need to set the environment variable OMP_NUM_THREADS suitably for this, you can experiment (and let me know how it works out, for reference).

67

Installation and License Questions / Re: Cannot assign more than 5 cores for AKMC

« Last post by Anders Blom on October 17, 2024, 08:09 »

You can not run more saddle searches concurrently than you have force field licenses. Now, normally each search can be parallelized with threads over many cores, however it seems this has not been implemented for force field calculators... I still have to double-check this with some people who are on vacation this week, and if there is a work-around, but for now just run on 6 cores (I don't expect 7 to work, but 6 should because it will have 1 dispatcher and 5 workers).

68

General Questions and Answers / Re: Grain Boundary Scattering doping problem

« Last post by Lim changmin on October 17, 2024, 06:46 »

Dear Anders Blom

Thank you for your advice.
I have some questions and a new issue while calculating the grain boundary.

1. From your reply, at number 6,7 is there a reason to calculate the total energy of relaxed structure? Can I just run over to 8,9 instead without calculating total energy?

2. I calculated a structure with 1e21 doping tag attached, and grain boundary scattering actually worked. But only for this structure. I tried other structures and they gave infinite resistance results.
I attached the py, log file and screenshot of the 1e21 doping structure results. As you can see, I calculated the grain boundary scattering with 1e21 doping and 0eV. But the calculation was successful.  Hope this might help.

69

General Questions and Answers / Compute Hall coefficient and Hall conductivity tensors

« Last post by physics on October 16, 2024, 09:07 »

Hello everyone,

Is there any tutorial available to compute Hall coefficient and Hall conductivity tensors?

Please let me know.

Thank you

70

General Questions and Answers / Re: Hall conductivity and Seebeck coefficient

« Last post by physics on October 15, 2024, 16:26 »

Please let me know about this.