Magnetic structure of Tm5Rh4Ge10

Neutron diffraction pattern recorded in the paramagnetic state confirmed that Tm5Rh4Ge10 exhibits tetragonal crystal structure of the Sc5Co4Si10 type. The Tb magnetic moments order below the Néel temperature of 6.9 K and form a sine-wave-modulated structure described by the propagation vector k=(kx, kx, 0). The value of kx changes from 0.216(1) at 1.5 K to 0.202(1) at 6.5 K. The Tm moments at three nonequivalent atomic positions are different but all are parallel to the c-axis.