Single Crystal Growth and Structural and Magnetic Properties of the Uranium Ternary Intermetallic Compound UCr2Si2

Abstract

We have grown a single crystal of UCr 2 Si 2 for the first time. UCr 2 Si 2 exhibits a structural transition from the ThCr 2 Si 2 -type ( I 4/ m m m ) to the triclinic structure ( P \bar1) below T a =210 K. The antiferromagnetic structure was determined by means of neutron diffractions, indicating the propagation vector \(Q=[-\frac{1}{2},\frac{1}{2},0]\) and the magnetic moment 0.65µ B /U oriented along the [0,0,1] direction. The high-field magnetization at 4.2 K indicates a metamagnetic transition at 11.4 T, reaching 0.65µ B /U at 14.9 T. The medium size of the electronic specific heat coefficient γ=80 mJ/K 2 mol, the magnetic entropy about half of R ln 2 at T N and a small effective moment 2.45µ B /U indicate that the antiferromagnetic state is due to 5 f -electrons with an itinerant character.