Calculation of the crystal-field parameters of Sm 2Fe 17N 3 from the measured temperature dependence of K1 and K2

For Sm ₂Fe ₁₇N ₃, the temperature dependence of the anisotropy constants K₁( T) and K₂( T) was determined from demagnetisation curves measured at different temperatures. Using the linear theory of magnetocrystalline anisotropy of 3d-4f intermetallics, the crystalline field parameters A₂₀ and A₄₀ were calculated from K₁( T) and K₂( T), and the 3d-4f interaction strength was estimated.