Phase transitions in two dimensions - the case of Sn adsorbed on Ge(111) surfaces

Abstract

Accurate atomic coordinates of the room-temperature (root3xroot3)R30degree and low-temperature (3x3) phases of 1/3 ML Sn on Ge(111) have been established by grazing-incidence x-ray diffraction with synchrotron radiation. The Sn atoms are located solely at T4-sites in the (root3xroot3)R30degree structure. In the low temperature phase one of the three Sn atoms per (3x3) unit cell is displaced outwards by 0.26 +/- 0.04 A relative to the other two. This displacement is accompanied by an increase in the first to second double-layer spacing in the Ge substrate.

RevTeX, 5 pages including 2 figures

Cited by in corpus (9)

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• The order-disorder transition of the (3x3)Sn/Ge(111) phase
• The order-disorder character of the (3x3) to (sqrt3 x sqrt3)R30&#176; phase transition of Sn on Ge(111)
• Determination of the (3x3)-Sn/Ge(111) structure by photoelectron diffraction
• A low temperature disordered phase of alpha-Pb/Ge(111)
• Surface Phase Transitions Induced by Electron Mediated Adatom-Adatom Interaction
• Charge-density-wave formation by Van Hove nesting in the α-phase of Sn/Ge(111)