Neutron diffraction studies of Tb2Rh3Si5 compound

In this work neutron diffraction studies of Tb2Rh3Si5 compound are reported. The compound crystallizes in the monoclinic crystal structure of Lu2Co3Si5-type. At 1.5 K an antiferromagnetic ordering with a propagation vector k=(1/2;1/2;1/2) was observed. The Tb magnetic moments of 9.8(2) μB form a non-collinear magnetic structure. In the vicinity of Néel temperature of 8 K a change of the magnetic ordering is evidenced. The change seems to be connected with phase transition from commensurate to incommensurate sine-wave modulation of the Tb magnetic moments.