Calculation of the electronic structure of formaldehyde using overlapping spheres in the SCF Xα scattered-wave method

It has recently been established that physical realism of the results can be improved within the framework of the self-consistent statistical exchange multiple scattering wave method if the atomic spheres are allowed to overlap. Here we report that by semi-empirically adjusting the overlap of the atomic spheres, the ionization potentials and total energy are in better agreement with experiment, and the order of levels A₁ and B₂ in formaldehyde is reversed with respect to some other calculations. The electronic energy level structure calculated here is in agreement with the experimental results. A systematic study of the overlapping scheme for formaldehyde is presented and the results are compared with experiments and other theoretical calculations.