Interferences in the photoelectron spectrum of H+2 molecules at high energy

We present a theoretical study of ground state H+2 ionization by photons of a few hundreds of eV. Bound and continuum states are obtained by using B-spline basis functions. As predicted by Cohen and Fano [H.D. Cohen, U. Fano, Phys. Rev. 150 (1966) 30], the calculated photoelectron spectrum reveals the existence of interference effects that result from the coherent emission in the presence of the two nuclei. We show, however, that one of the basic assumption of the Cohen-Fano model, namely, the validity of the LCAO approximation to describe the initial ground state or the free wave description of the ejected electron, is not fulfilled, which leads to an “anomalous” oscillatory behavior not pointed out in previous works.