Differential Thermal Analysis and Mössbauer Studies in Rare-Earth Orthoferrites

Curie temperatures of 14 different orthoferrites with the chemical formula RFeO3, (R = Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) were measured by differential thermal analysis. Hyperfine interactions of the Fe57 nucleus in the same materials were determined from their Mössbauer spectra. The quadrupole splittings (except for Sm), isomer shifts, Curie temperatures, and internal fields vary regularly with the ionic radius of R.