Phase diagram of UNiSn in magnetic field and under hydrostatic pressure

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