Navigation and service

Strongly anisotropic structure and magnetism of MnFe4Si3

Magnetic and structural properties of high quality magnetocaloric MnFe4Si3 single crystals are investigated macroscopically and on an atomic scale. Refinements of combined neutron and X-ray single crystal diffraction data introduce a new structural model in space group P (6) over bar characterized by partial ordering of Mn and Fe into layers perpendicular to c on one of the transition metal sites.
MnFe4Si3 has a phase transition to a ferromagnetically ordered phase at approximately 300 K and displays a strong anisotropy of the magnetization and the magneto caloric effect with the easy axis of magnetization in the a,b-plane. A refinement of the magnetic structure in the magnetic spacegroup Pm' shows that the spins on the sites with mixed occupancy of Mn and Fe are aligned in the a,b-plane. The thermal evolution of the lattice parameters exhibits an anisotropic behavior and clearly reflects the onset of magnetic ordering. A comparison of the ordered moment and the effective paramagnetic moment hints toward itinerant magnetism in the system.

Stucture and Magnetism

P. Hering et al., “Structure, Magnetism, and the Magnetocaloric Effect of MnFe4Si3 Single Crystals and Powder Samples”, Chem. Mater. 27,7128 (2015).

Contact: Karen Friese