Atomic Quadrupolar Photoemission Asymmetry Parameters from a Solid State Measurement

A method for measuring the asymmetry parameter $\gamma$ arising from dipole-quadrupole interference in core-level photoemission is proposed which is based on condensed thin films and exploits the influence of this asymmetry in photoemission monitoring of x-ray standing wave field absorption. The high density of material in this method offers some advantages over a conventional gas-phase measurement. Results are presented for C, O, and F $1s$ photoemission at photon energies around 3 keV. The combined nondipole asymmetry factor $(\delta +\gamma /3\mathrm{})$ for non- $s$-states can be determined in a similar way.