Phase diagram of UNiSn in magnetic field and under hydrostatic pressure

UNiSn exhibits an antiferromagnetic order in concomitance with a ferroquadr upolar order at the same transition temperature T-N similar to 43 K in zero magnetic held. We measured the magnetization, the thermal expansion, the e lastic modulus and the electrical resistivity as functions of temperature a nd magnetic field. The pressure dependence was also measured for the electr ical resistivity. The multiplex transition is observed to split when a magn etic or strain held is applied. (C) 1999 Published by Elsevier Science B.V. All rights reserved.