4f-3d interaction and magnetic anisotropy in ThMn12-type rare-earth transition-metal compounds

Rare-earth (R) transition-metal (T) compounds of the R(T,M)12-type with R = Y or one of the heavy-rare-earth elements, T = Fe or Co and M = Ti, V, Mo or Si, have been studied at 4.2 K in the Amsterdam High-Field Installation in magnetic fields up to 38 T and at temperatures between 4.2 and 1000 K in other magnetometers. The 4f -3d interaction is derived from magnetization measurements on single-crystalline particles that are free to rotate in the applied fields. The stabilizing element M is shown to have a pronounced influence on the 4 f -3d interaction strength in these compounds. The large variation in Curie temperatures of the Y compounds and the different types of magnetic anisotropy found in the Y compounds demonstrate that the element M plays an important role in establishing these properties as well.