CALCULATION OF HYPERFINE FIELDS IN BINARY Y-FE COMPOUNDS AND IN Y2FE14B

The Fermi contact contribution to the hyperfine fields on Fe nuclei in Y2Fe17, Y6Fe23, YFe3, YFe2, and Y2Fe14B has been calculated by means of first principles self-consistent band structure calculations. The calculated and experimental hyperfine fields are strongly correlated, but, similar to results reported earlier for elemental Fe, the absolute values of all calculated hyperfine fields are systematically too small. The 4s electron contribution to the hyperfine fields is shown to result in significant deviations from a simple proportionality relation between the hyperfine fields and the local Fe moments.