The phenomenon of magnetic compensation in the multi-component compounds (Tb,Y,Sm)Fe2 and their hydrides

The series of ferrimagnetic Laves-phase compounds (Tb,Y)0.8Sm0.2Fe2 obtained by gradual substitution of yttrium for terbium as well as the hydrides (Tb,Y)0.8Sm0.2Fe2H3.7 (amount of hydrogen close to the maximum allowed by the structure type) are investigated. We find that the MgCu2-type crystal structure is preserved after hydrogenation while the unit cell volume increases by ∼28%. The Curie temperature (TC) of hydrides is almost half the TC’s of the parent compounds. For (Tb1−xYx)0.8Sm0.2Fe2 with Y concentration x=0.6, we observe a magnetic compensation, i.e. mutual cancellation of magnetic moments of the sublattices, which is fully consistent with the model of a three-sublattice collinear ferrimagnet. In the hydrides (Tb1-xYx)0.8Sm0.2Fe2H3.7 the magnetic compensation occurs at x=0.2. In this case, we argue that a non-collinear magnetic arrangement is placement in the compound. We demonstrate that hydrogenation is a simple tool of changing the composition for which the phenomenon of magnetic compensation occurs.