Structure analysis of Ge(111)11-H by low-energy electron diffraction

The relaxation of the outermost Ge layers of the H-terminated Ge(111) surface is determined via low-energy electron diffraction intensity analysis. A contraction of the first interlayer spacing d12 by 0.100.05 A and a possible expansion of the second interlayer spacing d23 by 0.050.05 A is found. The influence of the H on the intensity curves is calculated and found to be negligible. A comparison with first-principles calculations is made and a mechanism is discussed that may explain the relaxation. © 1987 The American Physical Society.