[en] Highlights: • The potential of the Hg-CO₂ complex is developed. • The method is CCSD(T). • The dynamical calculate are performed. The first ab initio potential energy surface of the Hg-CO₂ complex was calculated using the single- and double-excitation coupled-cluster theory with a noniterative perturbation treatment of triple ex-citations [CCSD(T)]. The potential had a global minimum with energy −284.48 cm⁻¹ for a T-shaped geometry with $R=6.90a_0$. Using the potential, the bound states for five isotopomers of Hg-CO₂ complexes were calculated. The theoretical rotational spectra and molecular constants are all in good agreement with the experimental counterparts.