Second-order [ O(k2), k = ω/c] nondipole effects in soft-x-ray photoemission are demonstrated via an experimental and a theoretical study of angular distributions of neon valence photoelectrons in the 100–1200 eV photon-energy range. A newly derived theoretical expression for nondipolar angular distributions characterizes the second-order effects using four new parameters with primary contributions from pure-quadrupole and octupole-dipole interference terms. Independent-particle calculations of these parameters account for a significant portion of the existing discrepancy between experiment and theory for Ne 2p first-order nondipole parameters.
Atomic, Molecular and Optical Physics | Inorganic Chemistry | Physical Chemistry
Copyright American Physical Society. Used with permission.
Whitfield, S. B.,
Sellin, I. A.,
Johnson, W. R.,
Lindle, D. W.
Electric-octupole and pure-electric-quadrupole effects in soft x-ray photoemission.
Physical review letters, 84(10),