Spin polarization in low energy electron diffraction from Ni(001) and Ni(001) c(2×2)Te

Combined measurements of both electron spin polarization and intensity are described for several LEED beams from Ni(001) and Ni(001)c(2 × 2)Te surfaces. Polarizations and intensities were determined in the energy ranges 20–110 eV and 25–200 eV, respectively. Measurements on the specular 00 beam were undertaken at several angles of incidence in the range 10.2–18° for azimuthal angles φ = 0° and φ = 45°. The 01 beam, and the 1 2 , 1 2 beam from the Ni-Te surface, were studied at normal incidence. Sizable polarization features, ¦ P¦ ≲ 25%, were observed, even for Ni(001), indicating that polarized LEED measurements may be used to study surfaces of low atomic number. Pronounced changes in the polarization features were evident following deposition of a c(2 × 2) tellurium adlayer. The experimental data are in general agreement with the results of initial calculations undertaken using a relativistic multiple-scattering theory.