How to disable ECP?

Is there a way to disable the automatic usage of ECPs? I can only think of manually specifying a basis set definition without the ECP terms, but is kind of wasteful for built-in sets. Could BasisSet be manipulated?

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Basis sets designed to use ECP for certain elements won’t give sensible answers with only the non-ECP parts present. In particular the def2 basis usually have ECP for >Kr. There are a few bases that are all-electron for the heavy elements; Psi4 only defines sto-3g and 3-21g past Kr, I think.

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Now that X2C is in Psi4, it might make sense to try and grab the Dyall basis sets from DIRAC.

The nasty thing is that they’re not in an easily readable format…