SAPT2+ Calculations on K+, Rb+, and Cs+ complexes

I am trying to do energy decomposition analysis for complexes of K+, Rb+, and Cs+ with H2O. The aug-cc-pvdz is not compatible with the three ions. So I wounder what basis works best for these three metal ions.

Thanks a lot,

A def2- basis should run with SAPT, though ions, heavy elements, and ECPs with SAPT aren’t well explored.

In general I’d recommend using the aug-cc-pwCVnZ-PP basis sets for these elements (disclaimer: I was involved in the development of these basis sets), and ensuring you correlate the (m-1)sp electrons too. You can download them from the following website (select the Gaussian format for use in Psi4):

I would echo loriab’s warning though - no idea how well all of this will work in SAPT.

Thanks a lot GHill, I will look into it

Thanks Ioriab, for the info and the link.