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We have studied the surface and bulk plasmon losses associated with Li 1s photoemission. Here, full multiple scatterings of photoelectrons are taken into account before and after the plasmon losses within the quantum Landau formula that can describe overall features of the photoemission bands. We compared the depth profiles of the Li 1s single‐loss spectra with full multiple scatterings and without elastic scatterings. They are strongly influenced by the elastic scatterings. The model accounting for the full multiple scatterings gives a rapidly decaying function of the depth because of the defocusing effects. Copyright © 2014 John Wiley & Sons, Ltd.

We calculate the inelastic mean free path (IMFP) for small metal particles based on the plasmon model for free electron gas confined in small sphere with radius a. The IMFP decreases with the radius a smaller than about 100Å, and the rate of the decrease depends on the bulk plasmon energy ωp. We furthermore discuss the coordination numbers obtained from the EXAFS curve fitting method for small Ag particles. We find the importance of the size dependent IMFP for EXAFS analyses in order to obtain reliable coordination numbers in nanoparticles.

We study the energy-and angular-dependence of bulk and surface plasmon losses in low-and intermediateenergy region (< 1000 eV), and investigate the applicability of the quantum Landau formula which can explain overall plasmon loss features accompanied by core level photoemission. As an example, we calculate the Al 2s photoemission in the photoelectron kinetic energy range from 60 to 1000 eV measured at normal to the surface and at small take-off angles (10 • and 30 • ). For the normal emission the quantum Landau formula gives quite similar results to those without the high-enegy approximation even at 60 eV. On the other hand we observe the considerably large difference at the grazing angle emission (10 • ). Even at 30• we can safely apply the quantum Landau formula for the plasmon analyses above 250 eV.

Single plasmon losses associated with Al 2s photoemission have been theoretically studied on the basis of the quantum Landau formula, which describes overall features of x-ray photoelectron spectra. So far only photoelectron propagations from the emitters to the surface have been considered, and elastic scatterings have been completely neglected in studies of plasmon satellite peaks. This work takes all possible paths into account and includes elastic scatterings up to single scattering. The former causes rapid decay of the extrinsic loss intensity as a function of the emitter depth, and the latter emphasizes the photoemission from deep atomic sites.

Abstract. We have measured molecular-frame photoelectron angular distributions from carbon 1s and oxygen 1s levels of CO molecules up to a photoelectron kinetic energy (KE) of ~150 eV. The backward-scattering intensities exhibited a strong modulation as a function of the kinetic energy of the photoelectrons, whereas the intensities for the forward-scattering gradually increased and then became nearly constant over KE ~100 eV. Multiple scattering calculations with a muffin-tin potential qualitatively reproduced the experimental results. The present results may be considered as the observation of low-energy photoelectron diffraction patterns for gaseous free CO molecules, which are involved in modulations in extended X-ray absorption fine structure (EXAFS) spectra.

The Ginsburg-Landau equations are modified to include a magnetic permeability which varies with the order parameter \p according to the relation: ^= i u s^2 +ju n (l -\p 2 ). The influence of this on the predicted behavior of a superconducting film in a tangential magnetic field is investigated theoretically. A new value is derived for the upper limit of the critical field for a bulk superconductor and a thin film.