Facet Coexistence in the Roughening Transition of Ag(110)
We have studied the thermal behavior of the Ag(110) surface by synchrotron x-ray diffraction. In-plane diffraction data (Qz ≈ 0) agrees with earlier work and can be fit to a power law form. Out-of-plane data (Qz,max=0.7), however, indicates the existence of two coexisting phases below the roughening transition: flat (110) oriented regions separated by inclined rough regions. The relative coverage of these two phases is found to depend on the temperature. Thus, the roughening process can be viewed as a continuous replacement of the flat faceted regions by the rough phase. Using the Wulff construction, we are able to describe the temperature dependence of the relative phase concentrations and extrapolate to an estimate of the Ag(110) roughening temperature.
KeywordsTilt Angle Helium Atom Oriented Region Broad Component Free Energy Curve
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