Very Thin Oxide Layer on Fe Surface by Mössbauer Spectroscopy

A thin 57 Fe layer (20Å) was formed by UHV deposition on the surface of 56 Fe film (210Å). After exposure to air, Mössbauer and ESCA measurements were carried out. The results show that the oxide layer is fairly uniform with a thickness corresponding to about 12Å of Fe, and that the structure is close to γ–Fe 2 O 3 . The recoilless fraction of the thin oxide layer does not greatly deviate from the bulk value.