AUTOIONIZATION PHENOMENA INVOLVING THE 2P(5)3D CONFIGURATION OF ARGON-LIKE IONS IN IONIC SOLIDS

The photon-induced Auger and photoelectron spectra of the argon-like ions Cl- (in NaCl), K+ (in KCl), and Ca2+ (in CaCl2) have been measured in the vicinity of the L23 absorption edges of these ions. It is shown that at the 2p6 --> 2p(5)3d(4s) resonance, strong spectator and, in the cases of metal ions, participator effects appear in the electron spectra. The spectator structure is situated in the region of the L23M23M23 Auger spectra and shifts to higher kinetic energies with increasing photon energy. It originates from the 3p(-2)3d(4s) final configuration and arises as a product of the Auger-resonant inelastic scattering process of the incident photons. In the region of the L2 resonances the process includes the L2L3M45 Coster-Kronig transitions. The participator role of the excited 3d electron manifests itself as the resonant enhancement of the 3p and 3s photoelectron lines. The threshold energy for excitation of 2p electrons to the conduction band is about 202.5 eV for Cl in NaCl and 296.5 eV for K in KCl.