ELECTRONIC-PROPERTIES OF U2PT2SN

U2Pt2Sn is crystallizing in an ordered version (space group P4(2)/mnm) of the tetragonal U3Si2 type of structure. Clear anomalies in the mag netic susceptibility, specific heat, and electrical resistivity around 15 K indicate that U2Pt2Sn orders antiferromagnetically below this te mperature. As expected for an antiferromagnet, the susceptibility and specific heat anomalies are shifted to lower temperatures upon applica tion of external magnetic field. The specific-heat coefficient gamma=3 27 mJ/mol f.u. K-2 remains unchanged in fields up to 5 T. The antiferr omagnetic ground state of U2Pt2Sn can be concluded also from the metam agnetic transition around 22 T in the magnetization at 4.2 K and from magnetic reflections in the neutron-diffraction pattern at low tempera tures. (C) 1996 American Institute of Physics.