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 excitations [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. (C) 2017 Published by Elsevier B.V.