Magnetic structure of a UNiAl single crystal under pressure

Single-crystalline sample of UNiAl which orders antiferromagnetically below ¹ "19.3 K in a complex way (q"(0.1, 0.1 0.5)) has been investigated by neutron di!raction under pressure up to 4.9kbar. Although electrical resistivity measurements reveal a drastic change of the low-temperature transport properties around 3 kbar suggesting a change of the magnetic-structure propagation we have not found any indication for such a change. As the pressure increases, U magneticmoment magnitudes decrease slightly and the magnetic structure gets less perfect. However, the antiferromagnetic structure of UNiAl remains stable in the whole temperature and pressure range studied. 2001 Elsevier Science B.V. All rights reserved.