On the magnetic structure of Er2Fe14Si2

Elastic powder neutron diffraction experiments on the off-stoichiometric Th2Ni17-type Er2Fe14Si2 have been performed at temperatures between 10 and 593 K. In the paramagnetic state, a structural refinement revealed only small deviations from the statistical occupation of Fe on all four lattice sites. In the magnetically ordered state below Tc=478 K, a magnetic refinement was performed, too. Above the upper spin reorientation temperature Tsr1=110 K, a simple ferrimagnetic structure with an easy plane magnetization was found. In the temperature range Tsr1=110 K and Tsr2b=30 K, the moments tilt out of the plane. Below 30 K the magnetization is again easy plane, but with reduced Er moments. At ambient temperature, neutron diffraction experiments have been performed on the stoichiometric pseudobinary compound Er2Fe15Si2, too, in order to look for some influence of the deviation from the exact stoichiometry on the formation of the magnetic moments. (orig.)