An ab initio study on the bonding in H2CO3 and related species

In the current work we propose an elucidation of the electronic structure of carbonic acid, H2CO3 = (HO)(2)CO, through multi reference configuration interaction methods. We study the formation of both carbonic acid and related species like the parental H2CO species and the isoelectronic F2CO molecule along the X2C + O and 2X + CO C-2v paths (X = H, F, and OH). The participation of the excited states of their fragments appears to be transparent in the evolution of both the energy profiles and the non adiabatic coupling matrix elements of the corresponding states.