Figure 3. Interactions of CO with Na⁺ and Cl^– at the MP2/aVTZ level.

E_e is in kJ/mol at the CCSD(T)/CBS level; The shortest distance d_C/O from C/O to Na⁺/Cl^– at the (local) minimum energy potential is given in pm at the CCSD(T)/aVTZ level. Na⁺ has two minima along the C-e and O-e, while Cl^– has two identical minima nearly along the C-p.