Random distribution of islands explains the oscillatory intensity in He/Si(111)-(7 × 7)

It is shown that the oscillatory specular beam intensity observed in He/Si(111)-(7 × 7) scattering is consistent with a random distribution of islands of height ~3.05 Å. Each of these islands may be reconstructed, totally or partially, in a (7 × 7) structure according to the more favourable models proposed by LEED. This could be a possibility to explain, with the same (7 × 7) unit cell, He scattering and LEED experiments. © 1982.