The first potential energy surface and microwave spectra of the Hg–CO2 complex

Abstract The first ab initio potential energy surface of the Hg-CO 2 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 = 6.90 a 0 . Using the potential, the bound states for five isotopomers of Hg-CO 2 complexes were calculated. The theoretical rotational spectra and molecular constants are all in good agreement with the experimental counterparts.