Atomic quadrupolar photoemission asymmetry parameters from a solid state measurement

A method for measuring the asymmetry parameter gamma arising from dipole-qu adrupole interference in core-level photoemission is proposed which is base d on condensed thin films and exploits the influence of this asymmetry in p hotoemission monitoring of x-ray standing wave field absorption. The high d ensity of material in this method offers some advantages over a conventiona l gas-phase measurement. Results are presented for C, O, and F Is photoemis sion at photon energies around 3 keV. The combined nondipole asymmetry fact or (delta + gamma/3) for non-s-states can be determined in a similar way.