negative hydrogen ion

It is shown that the two-electron wave function of the system "hydrogen atom + photoelectron" in the Born approximation provides high accuracy of the photoionization process cross-section calculation of negative hydrogen ion.  The partial cross-sections, which correspond to different ``reaction ns-channels'' in the scale of photoelectron energy and the scale of wavelengths are calculated.  The comparisons with the results of other authors which obtained by other methods are performed.

In the frame of non-relativistic approximation, a compact approximate solution of the Schrödinger equation for the ion of $H^{-}$ has been obtained in the form of product for Legendre polynomials and variational functions of the Schull--Löwdin type. The accuracy of calculation of ion energy is of the same order that the results obtained using the multiparametric functions of Hylleraas and Pekeris.