Neutron diffraction study of uranium intermetallics: U(Fe1−xMnx)2Ge2, x=0.5, 1

Neutron diffraction (ND) measurements on U(Fe1-xMnx)2Ge2 with x=0.5 and 1 have been carried out in the temperature range 10-300K with a view to understand the nature of magnetic ordering and the effect of selective site substitution on magnetic moments. The profile analysis of the ND patterns shows that the moment on U is reduced to 0.5muB while muFe/Mn is 1.4muB, at 10K. It is also observed that the distance between U and transition metal site, dU-T is, reduced to 3.291A for UFeMnGe2 from a value of 3.364A for UMn2Ge2. We discuss these results in terms of hybridization between uranium 5f electrons and the transition metal 3d electrons resulting from the changed 3d environment and the distance dU-T, leading to a reduction or total suppression of the U moment.