M. Kuznietz et al., MAGNETIC-PROPERTIES OF U(NI1-XCUX)2SI2 SOLID-SOLUTIONS IN THE VICINITY OF X=0.50 STUDIED BY NEUTRON-DIFFRACTION AND AC-SUSCEPTIBILITY, Solid state communications, 87(8), 1993, pp. 689-693
The magnetic properties of two U(Ni1-xCux)2Si2 solid solutions in the
vicinitY of x = 0.50 (denoted I and II) have been studied by neutron d
iffraction and ac-susceptibility. Both materials have ThCr2Si2-type cr
ystallographic structure. AC-susceptibility shows antiferromagnetic tr
ansitions at T(N) = 150+/-5 K in UNiCuSi2(I) and 155+/-5 K in UNiCuSi2
(II), followed by several transitions with ferro/ferrimagnetic (F) cha
racter at lower temperatures. Apart from the transitions to AF-I struc
ture (+ - + -) at T(N) (150+/-1 K and 152+/-2 K, respectively), none o
f the F transitions is observed by neutron diffraction. Short-range ma
gnetic order, involving several consecutive ferromagnetic planes or fe
rrimagnetic groups of planes in the AF-I phase,detected by ac-suscepti
bility and not by neutron diffraction in both materials and therefore
significant to x almost-equal-to 0.50, is proposed to explain the unus
ual susceptibility.