Crystal field in nitrogenated rare-earth intermetallics

Authors

Ralph Skomski, University of Nebraska-LincolnFollow
M.D. Kuz'min, Trinity College, Dublin, Ireland
J.M.D. Coey, Trinity College, Dublin, Ireland

Date of this Version

May 1993

Comments

Published by Am Inst of Physics. J. Appl. Phys. 73 (1993) 6934-6936. Copyright 1993. Permission to use. http://www.aip.org/.

Abstract

The crystal-field in Sm₂Fe₁₇N_{3- δ} and Sm(Fe₁₁Ti)N_{1- δ} due to interstitial nitrogen has been investigated. Intrinsic parametrization in the superposition model allows separation of the crystal field created by a neighboring nitrogen atom from a purely geometrical factor, which is different for Sm₂Fe₁₇N_{3- δ} and Sm( Fe₁₁Ti) N_{1- δ} Using published magnetic data, values for the intrinsic parameter A₂ per nitrogen atom of A₂=200± 60 Ka₀^-2 and A₂=270±60 Ka₀^-2 for Sm₂Fe₁₇N_{3- δ} and Sm(Fe₁₁Ti)N_{1- δ}, respectively, are obtained. Because of charge penetration, which is discussed in the form of an explicit crystal-field weight function, it is not possible to interpret A₂⁰ or à ₂ as crystal-field parameters independent of the 4f ion.