A study of the surface reconstruction of Y(11•0) had shown a sixfold-symmetrical low-energy electron diffraction pattern in contrast to the twelvefold-symmetrical pattern reported earlier. This indicated that only one orientation of close-packed atoms existed on the surface; the collapse of the surface unit cell was uniaxial along the (00•1) direction. This produces the same commensurate surface structure as found previously for the (11•0) (7 x 1) reconstructions of Ho and Er. Why the earlier study of Y showed a two-domain reconstruction had not been determined, but they suggest that this structure was influenced by the presence of surface defects, inducing the collapse of the unit cell along the (10•0) direction to form an incommensurate domain with approximately equal probability to that of the commensurate (7 x 1) domain.

Observation of a (7 x 1) Surface Reconstruction on Y(1120). S.D.Barrett, R.I.R.Blyth, S.S.Dhesi, K.Newstead: Journal of Physics - Condensed Matter, 1991, 3[12], 1953-6