Magnetic structure and spin reorientation of quaternary Dy₂Fe₂Si₂C

Abstract

We have investigated the low temperature magnetic properties of DyFeSiC by using magnetisation, specific heat, x-ray diffraction, neutron powder diffraction and Fe Mössbauer spectroscopy measurements over the temperature range 1.5 K-300 K. DyFeSiC exhibits two magnetic transitions at low temperatures: an antiferromagnetic transition at [Formula: see text] K and a spin-reorientation transition at [Formula: see text] K. The magnetic structure above T can be described with a propagation vector [Formula: see text] with the ordering of the Dy magnetic moments along the monoclinic b-axis whereas on cooling below T the Dy moment tips away from the b-axis towards the ac-plane. We find that the spin-reorientation in DyFeSiC is mainly driven by the competition between the second-order crystal field term B and the higher-order terms, in particular B and B .