Vibrationally resolved photoelectron angular distributions from randomly oriented and fixed-in-space N-2 and CO molecules

Vibrationally resolved photoelectron angular distributions from randomly oriented and fixed-in-space N-2 and CO molecules have been evaluated by using an extension of the static-exchange density functional theory that includes the nuclear motion. Both K-shell and valence-shell photoionization have been considered. Comparison with the experimental data, only available for randomly oriented molecules, is very good. Our predictions for molecular-frame photoelectron angular distributions of N-2 show the signature of electron confinement and coherent two-centre interferences as those previously found in H-2. For CO, they exhibit diffraction patterns associated with the scattering of the ejected electron by the neighbouring atomic centre. The conclusions reported in this work suggest that vibrationally resolved photoelectron angular distributions can be a useful instrument to determine structure parameters in these simple molecules.