Error when reading MAPI Key

This may be a PyCDT question, but the error is attributed to MPRester.

It should be read from the .pmgrc.yaml file but I am assuming from the error that the file may not be found. I’ve seen two different ways for the file to read the API key. Either,


I have both in the file now and neither are read.

Any advice is welcome. Thank you.

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Have you double-checked that you updated the pmgrc.yaml file with the correct API key (from your MP account)?

Yes, I have check it is the correct key.

New users can only place one image in post so here is the code producing the error,


I see. Is the yaml file located in your home directory?
Anyway, for the time being, you could just explicitly specify the key in your code:

cpa = MPChemPotAnalyzer(mpid='mp-2534', mapi_key='pasteyourmapikeyhere')
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That worked for me, thank you!

The .pmgrc.yaml is in the %USERPROFILES% directory. It was auto written there.

You can also use:

from pymatgen import SETTINGS

to see if your .pmgrc.yaml file is being used correctly. I believe setting PMG_MAPI_KEY as an environment variable should also work.

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@mkhorton, it looks like my SETTINGS are empty, so with that I don’t think my .pmgrc.yaml file is being read.