The structure and stability of the O:+ dication: a dramatic failure of Marller-Plesset perturbation theory
نویسندگان
چکیده
By comparison with results of full configuration-interaction and large-scale multireference configuration-interaction calculations, it is shown that the widely used RMP2 and RMP4 methods fail to describe even qualitatively the structure and kinetic stability of theO:+ dication, an isoelectronic analogue of molecular nitrogen. A barrier todissociation of more than 200 kJ mol-’ completely disappears. In contrast, much better results are obtained from other methods based on a single reference function, such as quadratic configuration interaction and the Brueckner doubles procedure.
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