Cation distribution and IR spectra of rare-earth gallium iron garnets

The Mössbauer and IR measurements of the R 3 Fe 5- z Ga z O 12 garnets, where R = Lu, Yb, Er, Y, Gd, Sm and 0 ⩽ z ⩽ 5, indicate a tendency of decreasing tetrahedral site preference of Ga with increasing size of the dodecahedral cation.