Novel structural phases of Dy thin films on W(1 1 2)

Thin films of the rare-earth metal Dy were grown on W(1 1 2) at room temperature and 570 K. Then the resultant film morphologies were characterised by LEED and STM. A series of novel film morphologies, including c(4 × 6), c(5 × 12) and (5 × 8) structures, were found that are unique among the rare-earth metals. High thermal stability was found for the Dy films (up to 1650 K, close to the melting point at 1685 K) such that the Dy atoms preserved an ordered structure and the Dy volatility was less than would be expected from its vapour pressure. This is an indication of strong electronic interactions between the Dy atoms and the W(1 1 2) substrate.