FE-57 MOSSBAUER-EFFECT IN UFEXAL12-X SYSTEM

Fe-57 Mossbauer effect examinations were carried out on UFexAl12-x all oys with x=4, 5 and 6 in the temperature range 14-370 K. The spectra f or x=5 and 6 can be fitted with the Fe atoms distributed over the 8(f) , 8(j) and 8(i) positions, whereas for x=4 the Fe atoms are located at the 8(f) sites only, in agreement with earlier results. The hyperfine fields corresponding to the three sites (f, j, i) are 54%, 43% and 3% for x=5 and 58%, 35% and 7% for x=6 respectively. The Curie points de termined from H-hf(T) plots are 162, 265 and 350 K for x=4, 5 and 6 re spectively, in fair agreement with the results of magnetic examination s.