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Photoelectron spectra of gas-phase molecules display sharp vibrational structure. The envelope of the spectrum is determined by the Franck-Condon factor. On the other hand, photoelectron spectra of the same molecules, adsorbed or condensed onto metal
Measurements are made of the transmission of medium energy electrons through in vacuo deposited films in order to determine the inelastic electron mean free path as a function of energy. Films of Al, Ge and Au are deposited in small increments on 20-30 ¿
The angular distribution of electrons ejected in core-valence-valence Auger transitions of atoms chemisorbed on metal surfaces is considered theoretically. Since the valence electrons participating in the Auger transition are also involved in chemical
Photoelectron spectra (hv = 21.22 eV) and thermal desorption data were obtained for CO and H coadsorbed on W(100) at 80 K. When the clean surface is exposed to a saturation dose of H2, subsequent exposure to CO results in the formation of a state whose
Relativistic Hartree-Fock-Wigner-Seitz band calculations have been performed for the actinide metals Ac through Bk in order to estimate the Coulomb term U and 5 f electron excitation energies. Our calculations predict that the tetravalent state (four 6 d-7
Screening or polarization energies (often called "extra-atomic relaxation energies") associated with localized-hole creation in photoelectron spectroscopy in or on metals have been calculated. Following the procedure of Hedin and Lundqvist, the screening
It is shown that the primary contribution to the field-emission current comes from electrons with total momentum equal to zero in a direction parallel to the metal surface and that the field-emission current measures the density of states at a point
By means of soft-x-ray photoemission Citrin and Hamann have observed core level shifts of Ne, Ar, Kr, and Xe atoms implanted in the noble metals and have constructed a theoretical model with which to interpret the results. We describe calculations
Mean free paths for electrons in bulk jellium are calculated for electrons with energies from a few hundred to a few thousand eV and for values of r s for 1.5 to 5 where r s is the average distance between valence electrons measured in units of the Bohr
A microwave-discharge uv light source has been improved to yield significant photon fluxes at 26.9 and 40.81 eV. In order to optimize the 26.9-eV (NeII) and 40.81-eV (HeII) radiation, the discharge was operated at ~2.5 Pa (0.019 Torr) in an external
We present estimates of various contributions to the free-atom-metal binding-energy shifts, Δ}E B, for the 2>s and 2p core levels of teh iron series elements and, for comparison, the 3 d s/2 level of Sn. Our results indicate that the sharp break in the
We describe calculations of 4f electron binding energies for the rare-earth metals. Relativistic Hartree-Fock calculations for atomic configurations most closely approximating those of the metals are initially performed, and crystal potentials are
R E. Watson, J F. Herbst, L Hodges, B I. Lundqvist, J W. Wilkins
Self-consistent energy-band calculations for paramagnetic Ni have been performed in an effort to compare ground-state and excitationpotential prescriptions; potentials of the Hartree-Fock-Wigner-Seitz and Hedin-Lundqvist type are examined. We find the
A survey is given of the available cross-section data for ionization of inner-shell electrons by incident electrons in the range of interest for electron-probe microanalysis and for Auger-electron spectroscopy of solid surfaces. Owing to the paucity of
Mean free paths for electrons in bulk jellium are calculated for hot electrons with energies from a few hundred to a few thousand electron volts and for values of r s from 1.5 to 5. Exchange and correlation effects are included and the results are compared
Electron spectroscopy for chemical analysis (ESCA) can be used as a quantitative tool for the determination of the chemical composition of the surface region of a solid if certain parameters are known. The least well known is the electron mean free path