SN-119 MOSSBAUER STUDIES OF THE UCU1-X(X=0,0.1) SYSTEM(XSN1)

Sn-119 Mossbauer measurements were taken of UCu1+xSn1+x (x=O, 0.1) sam ples over a wide temperature range (4.2-300 K). Careful analysis of th e obtained results revealed that the non-centric GaGeLi structure type with space group P6(3)mc is correct for the U-Cu-Sn phases. UCuSn and UCu1.1Sn0.9 phases order antiferromagnetically. A magnetic structure with an antiferromagnetic wave vector lying close to the basal plane a nd with ferromagnetic coupling along the c axis with the net magnetic U moment near that plane is proposed. The collinear alignment of the m agnetic U moments in the basal plane as well as collinear ordering alo ng the c axis were excluded.