8.16 A Brief Guide to Q-Chem’s Built-In ECPs

8.16.8 The Karlsruhe “def2” ECP at a Glance

(May 16, 2021)

For elements Rb–Rn, all the Karlsruhe “def2” basis sets are paired with a common set of ECPs. 1154 Weigend F., Ahlrichs R.
Phys. Chem. Chem. Phys.
(2005), 7, pp. 3297.
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It is briefly summarized in the table below (the number of valence basis functions depend on the basis set in use, so it is not presented):

Element Core Max Projector
H–Kr none none
Rb–Xe [Ar]+3d D
Cs–La [Kr]+4d D
Hf–Rn [Kr]+4d+4f D
Table 8.18: Supported elements for the def2 ECP.