Lowhyphen;Energy Electron Diffraction Study of Tungsten (100) Surface

摘要

The diffraction of electrons by a tungsten (100) surface was studied in a displayhyphen;type LEED apparatus. The sample surface was cleaned by repeatedly heating to 2300deg;K in high vacuum. Instrumental factors and the effect of adsorption of ambient gases on intensities were checked. The 00 beam intensity profile was measured in the energy range 100ndash;300 eV for sequences of primaryhyphen;beam orientations. Special effects associated with the simultaneous occurrence of different Bragg conditions were found. A tabulation of energies and orientations at which simultaneous Bragg conditions occur is presented.