On the transferred hyperfine interaction in substituted yig

NMR of⁵⁷Fe is studied in a number of (M_xY_3–x) Fe₅O₁₂ garnets for small concentrations of M (M is either trivalent RE ion –Ho 3+, Gd 3+, Nd3+, Pr 3+, La 3+ or Bi 3+ ion). Beside the main resonance lines, the satellites were observed, which correspond to those Fe, in vicinity of which the impurity M is located. After correcting for the dipolar field, the field corresponding to the change of the transferred hyperfine interaction in M³⁺–O^2–-Fe³⁺ vs. Y³⁺–O^2–-Fe³⁺ triad was deduced from the satellites splitting. The analysis of the results indicates that the observed change in the transferred hyperfine field is mainly connected with the transfer of electrons between M³⁺ and Fe³⁺ ions and not with the local deformation around the impurity.