BoltzTraP error

Hello users,

I am trying to calculate the electronic transport properties using the boltztrap module of the electronic structure package. My attempt is uploaded in this github page

The error I get is the common factorisation error, which occurs due to low k-grid.

Can someone please identify, what I need to do in this code to correct this error?

George Yumnam

It looks like you are trying to run BoltzTraP using line-mode band structures. The band structures returned from MPRester are across high-symmetry lines in k-space only.

For running BoltzTrap, you need the eigenvalues from a dense uniform k-mesh. MP computes these and has the data but has not made this available through the REST interface. There is some votes for this capability inside the “request features” of MP.

The future plan is to open up the uniform k-mesh band structures on the MP platform very soon. We are going to submit a paper on the results of our Boltztrap calculations so far and at the same time allow users to download uniform k-mesh band structures from MP. You could then feed those band structures into Boltztrap.



I was interested in using this transport data, and located it in the Dryad repository. But, I was just wondering whether the data has since been made available through the REST API interface.

Thank you,

Hi Ramya,

Thank you for your interest in our BoltzTraP data. Francesco Ricci, who uploaded the data to the Dryad repository, has also contributed it to MP through our new MPContribs platform:

Log in with your Google account and click on to the Carrier Transport data set.

Documentation to programmatically retrieve contributed data via the MPContribs API is at

Click the “launch binder” badge in the “Tip” section, to start an example Jupyter notebook for the carrier_transport data on BinderHub. This doesn’t require any installation and you can download the notebook as well as the data you need afterwards.

You are one of the very first ones we’re referring to this new infrastructure. So, happy to hear your feedback, and please let me know if you have any questions or run into any issues.


Hi Patrick,

Thanks again for the information, We have been using MPContribs and it has been working well for us. I have using the “contributions” endpoint, but originally had some difficulty choosing between the “contributions” and “tables” endpoint. If I remember correctly, I had originally wanted tabular data, but also wanted to be able to search by contribution ID for a single entry. However, I had found that difficult with the tables endpoint.

I had a couple things to note specifically regarding the “Carrier Transport” database. For the “modal properties,” I do not believe the temperature and carrier concentration that give the modal value are available yet, unless I happen to be missing something. Will this information be added soon? Additionally, the modal value for the conductivity effective mass seems to be the maximum value, but in the thermoelectric quality factor, this value should actually be minimized.

Thanks gain for the support and the helpful tool!

Hi Ramya,

sorry for the late reply. We’ve been very busy at MP with our annual workshop.

I’m glad MPContribs has been working well for you and I’m always happy to hear feedback :slight_smile: Can you give me a specific example of a query that has been difficult to achieve? I’ll try to improve the API or give pointers.

The temperature and carrier concentration are given in the description I believe:

The values reported are the eigenvalues and their average at a doping level of 10¹⁸ cm⁻³ and at a temperature of 300 K

The original contributor, Francesco Ricci (@fraricci), should be able to answer any (other) questions you have about the dataset.


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