کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5360778 | 1388265 | 2008 | 4 صفحه PDF | دانلود رایگان |
We studied the structures and the phase transition of Pb/Ge(1Â 1Â 1) surface by using the reflection high-energy positron diffraction. The surface structures at 60Â K and 293Â K have the 3Â ÃÂ 3 and â3Â ÃÂ â3 periodicities, respectively. The rocking curves measured at both temperatures are nearly the same. This indicates that the equilibrium positions of the surface atoms do not change according to the phase transition. From the analysis of the rocking curve based on the dynamical diffraction theory, we found that at both temperatures the surface structures are composed of the so-called one-up and two-down model. The 3Â ÃÂ 3-â3Â ÃÂ â3 phase transition for the Pb/Ge(1Â 1Â 1) surface is interpreted in terms of order-disorder transition.
Journal: Applied Surface Science - Volume 254, Issue 23, 30 September 2008, Pages 7827-7830