Assessment of B3LYP combined with various ECP basis sets for systems containing Pd, Sn, and Pb

► Various ECP basis sets are evaluated for Pd, Sn, and Pb. ► The assessment is based on the calculated properties of diatomic molecules. ► LANL2TZ(f) for Pd and LANL08d for Sn and Pb are recommended. ► These can be used to study the semihydrogenation of alkynes on Pd-Sn and Pd-Pb.