Surface alloy formation and two-dimensional vitrification in adsorbed monolayers on (112) molybdenum surface

By means of low-energy electron diffraction, scanning tunneling microscopy, contact potential difference and Auger electron spectroscopy methods we observed the formation of surface alloys under annealing of Dy, Gd, Sr, and Be monolayers adsorbed on the Mo(112) surface. The surface alloys are formed as nanodispersed systems of oligomer clusters in the Dy and Sr films, and as a continuous coverage in the Be and Gd ones. The Dy films, forming Dy - Mo surface alloy on annealing, are shown to undergo a transition to a two-dimensional glass state on subsequent cooling (hardening) to low temperatures while the surface alloys of Be and Gd with Mo(112) are formed in a crystal state.