Electronic structure and surface reconstruction of DyNi films grown on W(1 1 0)

Angle-resolved photoemission and low-energy electron diffraction (LEED) were used to study thin films of DyNi(0 0 1) grown in situ under ultra-high vacuum conditions by codeposition of Dy and Ni onto a W(1 1 0) substrate and subsequent annealing. Guided by the results of electronic structure calculations an observed (3×1) overstructure of the LEED pattern and the appearance of a Dy 5d-derived surface state at the Fermi energy are explained by a reconstruction of the (0 0 1) surface resulting from missing Ni rows in the topmost atomic layer. Similar to metallic Gd(0 0 0 1) the d-like behavior of the obtained surface state may influence surface magnetic properties of thin films of DyNi.