An57Fe Mössbauer study of rare-earth intermetallic compounds R(Fe11Ti)

⁵⁷Fe Mössbauer spectra are reported for the ThMn₁₂ structure series of intermetallic compounds R(Fe₁₁Ti) (R=Y, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Lu). The Mössbauer spectroscopy of oriented absorbers has been used to study the spin reorientation transitions exhibited by the members of the series where the second-order Stevens coefficient α_J of the rare-earth (Nd, Tb and Dy) is negative. A simple model has been established to deduce the canting angle from the Mössbauer spectra of oriented absorbers. The results are analyzed in terms of a crystal-field model. The crystal field parameters must be increased significantly to account for the observed large anisotropy in the Sm(Fe₁₁Ti) compound, which may find applications as a permanent magnet.