Magnetic ordering in UNiSi2

Abstract Neutron diffraction and magnetization studies have been carried out on the intermetallic compound UNiSi 2 . The diffraction data confirm the orthorhombic CeNiSi 2 type structure reported earlier for this compound. The present magnetization studies show that UNiSi 2 orders ferromagnetically below 97 K and that there is no indication of any antiferromagnetic component down to 2 K. The low temperature neutron diffraction data show collinear ferromagnetic ordering, with the U-moments directed along the shorter ( c )-axis. The value of the magnetic moment on uranium atoms is found to be 1.2  μ B .