What can we get From LEED?

LEED is the principal technique for the determination of surface structures. It may be used in one of two ways:

1.Qualitatively: where the diffraction pattern is recorded and analysis of the spot positions yields infor on the size, symmetry and rotational alignment of the adsorbate until cell with respect to the substrate unit cell.

2.Quantitatively: where the intensities of the various diffracted beams are recorded as a function of the incident electron beam energy to generate so-called I-V curves which, by comparison with theoretical curves, may provide accurate info on atomic positions.

Experimental Equipments

In our lab, a commericial spectrometer with back display LEED-AUGER optics have been assembled in the Preparation Charmber as shown in Figure 1.