Determination of crystal-field parameters of Sm₂Fe₁₇N₃ and Sm₂Fe₁₇C₃

Authors

S. Wirth, Institut fur Festkorper- und Werkstofforschung Dresden
M. Wolf, Institut fur Festkorper- und Werkstofforschung Dresden
K.H. Muller, Institut fur Festkorper- und Werkstofforschung Dresden
Ralph Skomski, University of Nebraska-LincolnFollow
S. Brennan, Trinity College, Dublin, Ireland
J.M.D. Coey, Trinity College, Dublin, Ireland

Document Type

Article

Date of this Version

September 1996

Comments

Published in IEEE TRANSACTIONS ON MAGNETICS, VOL. 32, NO. 5, SEPTEMBER 1996.

Abstract

The crystal-field parameters A₂₀ and A₄₀ were determined from the magnetocrystalline anisotropy constants K₁ and K₂ in a linear approximation for Sm₂Fe₁₇Z_x (Z = N, C) compounds. For the materials investigated, the values of Iη0 are calculated in two ways: i) from the Kί at zero temperature and ii) from the temperature dependence of the Kί. Both methods give equivalent results. The value A₂₀≈-400 Ka₀^-2 has been obtained which corresponds to an inverse THOMAS-FERMI screening length q≈2.3 Å^-1 calculated within the framework of the screened charge model.