Matrix isolation far-infrared spectra and thermodynamic properties of binary and mixed cadmium dihalides

Chemically Accurate Thermochemistry of Cadmium: An ab Initio Study of Cd + XY (X = H, O, Cl, Br; Y = Cl, Br)

Using a composite coupled cluster method employing sequences of correlation consistent basis sets for complete basis set (CBS) extrapolations and with explicit treatment of core-valence correlation and scalar and spin-orbit relativistic effects, the 0 K enthalpies of a wide range of cadmium-halide reactions, namely, Cd + (HCl, HBr, ClO, BrO, Cl2, BrCl, Br2) have been determined to an estimated accuracy of +/-1 kcal/mol. In addition, accurate equilibrium geometries, harmonic frequencies, and dissociation energies have been calculated at the same level of theory for all the diatomic (e.g., CdH, CdO, CdCl, CdBr) and triatomic (CdHCl, CdHBr, CdClO, CdBrO, CdCl2, CdBrCl, CdBr2) species involved in these reactions, some for the very first time. Like their mercury analogues, all of the abstraction reactions are predicted to be endothermic, while the insertion reactions are strongly exothermic with the formation of stable linear, Cd-centric complexes. With the exception of CdH and the reactions involving this species, the present results for the remaining Cd-containing systems are believed to be the most accurate to date.