Oxygen-induced nano-faceting of Re( 11 2 ¯ 1 )
We report results from a detailed study of oxygen-induced faceting of Re(112¯1) using low energy electron diffraction (LEED). Depending on conditions for reaction with oxygen, the initially planar Re(112¯1) surface evolves sequentially to form zigzag chains consisting of (011¯0) and (101¯0) facets that coexist with stepped (112¯1) plateaus; three-sided pyramids exposing (011¯0), (101¯0) and (336¯4) facets; a faceted surface with five facets including (011¯0), (101¯0), (112¯2)-(2 × 1), (011¯1)-(2 × 1) and (101¯1)-(2 × 1); and four-sided pyramids exposing {011¯0} and {011¯1}-(2 × 1) facets. We have observed reversible morphological transitions between the faceted surfaces and discovered that each intermediatemore »