How to select a functional with SAPT module

I am new to psi4. I needed to inquire, if it is possible to specify a functional of our choice when we just want the sapt calculations. If so what is the correct way to do it. None of the given examples in the /samples directory /sapt1 mention it.
Also it would be nice to know the default functional psi4 uses when running sapt calculations.

You needed to look for the sapt-dft samples. You can specify a functional like so.

Looking at the test suite tells me that PBE0 is the default functional.

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Thanks a lot for your answer. This was really helpful. I need to clarify two more things , which might be pretty basic, but i am in the dark here.

  1. Does the choice of functional affect the sapt results … i mean…What is the actual diff b/w a sapt call and a sapt(dft) call ?

  2. Can gaussian generated .fchk files be used as input in psi4 ?

  1. They’re not all exactly the same, but the original (non-psi) dft-sapt developers tried a few and decided this wasn’t an area the method zoo would profit by expansion.

  2. Sorry, no, not at present.