The (aug-)cc-pVXZ calculations were performed with Orca 5.0.3 , or for the larger systems and augmented bases with Turbomole V7.1 after checking that both programs give identical results. The HF wavefunction and energies are obtained for all-electron calculations, while the frozen-core approximation is used for the MP2 correlation energy, i.e. occupied orbitals corresponding to core electrons are omitted in the MP2c evaluation. The convergence threshold for the SCF wavefunction was set to VeryTightSCF for Orca, respectively to 10 -7 a.u. for the energy gradient in Turbomole.