Studiu teoretic al cei mai stabili izomeri ai moleculelor IO3și HIO3

Abstract

In the present work the qualitative features of the electronic structure of the XO3− and HXO3 molecules, their possible spatial structures and the form of the adiabatic potential energy surfaces (APES) of these systems in the neighborhood of their high-symmetry D3h and C3v nuclear configurations are considered from the vibronic theory point of view. The electronic structure calculations were carried out by ab initio SCF CI method with the use of the extended basis sets. Parameters of the pseudo Jahn-Teller effect were estimated by fitting the ab initio calculated data for the APES of the XO3− and HXO3 to the general formula of the vibronic theory. It is shown that the reason of the instability of their high-symmetry nuclear configurations is the PJT coupling between the ground and appropriate by symmetry excited electronic states.