Magnetic ordering in RCoSn ( R = Dy, Ho, Er) compounds

Abstract

Magnetic and crystal structures of DyCoSn, HoCoSn and ErCoSn were determined by neutron diffraction on polycrystalline samples. All crystallize in the orthorhombic, TiNiSi type of structure and order antiferromagnetically below the following Néel points: 10 K (DyCoSn), 7.8 K (HoCoSn) and 5 K (ErCoSn). Magnetization against magnetic field strength curves indicate a magnetic phase transition occuring at H = 0.26 and 0.35 T in DyCoSn and HoCoSn, respectively. The magnetic structures of all three compounds are square modulated with the wavevector k = [0, k y , 0], where k y is 5 7 , 2 3 and 7 11 in DyCoSn, HoCoSn and ErCoSn, respectively. The noncollinear ordering can be described by the A and G modes in terms of the Bertaut method.