Magnetic order in an MnF2 epitaxial layer with the orthorhombic structure

The magnetic structure of MnF2 is determined by the neutron diffraction method in the metastable orthorhombic phase grown in the form of thin (similar to 1 mu m) film on a CaF2 buffer layer by the molecular beam epitaxy method. The magnetic moments of Mn++ form a simple two-sublattice antiferromagnetic structure and are directed along the c crystallographic axis parallel to the film plane. Using the temperature dependence of magnetic reflections, a Neel temperature of 67.19(7) K and a critical index of 0.50(2), which corresponds to the mean field approximation, are determined.