HIGH-RESOLUTION LOW-ENERGY ELECTRON-DIFFRACTION CHARACTERIZATION OF RECONSTRUCTED AU(001) SURFACES

The reconstruction of Au(001) surfaces was characterized by using high resolution low energy electron diffraction through an accurate measurement of the Bragg positions of the diffraction beams. The reconstruction hexagonal overlayer was determined to have in-plane contractions of ∼ 3.6% and ∼ 19% along two orthogonal directions of the square lattice of the underlayer. These contractions result in a (28 × 5) superlattice. The step density and direction were estimated from the angular profiles of integer order beams. This finite terrace width and step direction select the preferred growth of one of the orientational reconstruction domains. From the measurement of angular profiles and relative intensities of superlattice beams, the alignment of the 28-fold reconstruction direction with the step edges was deduced. © 1990 Elsevier Science Publishers B.V. (North-Holland).