Photoionization of oriented molecules: a time dependent density functional approach

The B-spline time dependent density functional one center expansion method is employed to calculate the photoelectron angular distribution for the K-shell photoionization of the oriented CO molecule. Good agreement between theory and experiment is gained for both parallel and perpendicular polarization. Observed discrepancies are ascribed to double excitations not included in the theoretical model. The quality of the results is comparable or even better than the quality of ab-initio relaxed core Hartree Fock (RCHF) data. The computational economy and the generality of the method makes it a good candidate for further studies for core and valence photoionization of oriented polyatomic and less symmetric molecules.