Core-level electronic structures of rare-gas atoms implanted in transition metals studied by XPS and XAES

Abstract

The electronic structures in core levels have been investigated for rare-gas atoms (Ne, Ar, Kr, Xe) implanted in a series of 3d transition metals. The extra-atomic relaxation energies of the core-electron emission were estimated from X-ray photoelectron spectra (XPS) and X-ray-induced Auger electron spectra (XAES). It was found that the extra-atomic relaxation energies for neon and xenon in 3d transition metals increase with the number of d electrons in the matrix metals, and the values for xenon are larger by 1–2 eV than those for xenon adsorbed on metal surfaces. It was also elucidated that the magnitudes of the relaxation energies for rare-gas atoms in the same metal matrix increase with the atomic radii of the rare-gas atoms. These findings are discussed in relation to the screening of core holes by d electrons of the matrix metals.