Amorphous Rare-Earth - Iron Alloys Below the Curie Point by Moessbauer Effect.

Mossbauer studies were made on bulk amorphous samples of the R(Y, Tb, Ho, Er, Tm)-Fe alloy series, prepared by dc rapid sputtering techniques. The temperature range of the studies was from room (295 K) to liquid helium (4.2 K). A spin glass-like Curie temperature of 55 K was established for a-YFe2, from the temperature dependence of the hyperfine field and zero relative velocity, single channel, count. The time averaged, magnetic hyperfine field at 4.2 K has been determined for the majority of the samples as follows: a-YFe2, 233 + or - 6 kOe; a-HoFe2, 209 + or - 14 kOe; a-ErFe2, 148 + or - 21 kOe; and an estimate for a-TmFe2, 150 + or - 30 kOe. The film value of a-YFe2 is about 60 kOe lower than the bulk value reported here and scales better by DeGennes factor in the a-RFe2 series. The bulk value, on the other hand, scales better with the a-RFe2 values if their atomic radii are used.