Magnetic properties of EuLn2O4 (Ln = rare earths)

Ternary rare earth oxides EuLn(2)O(4) (Ln = Gd, Dy-Lu) were prepared. They crystallized in an orthorhombic CaFe2O4-type structure with space group Pnma. Eu-151 Mossbauer spectroscopic measurements show that the Eu ions are in the divalent state. All these compounds show an antiferromagnetic transition at 4.2-6.3K. From the positive Weiss constant and the saturation of magnetization for EuLu2O4, it is considered that ferromagnetic chains of Eu2+ are aligned along the b-axis of the orthorhombic unit cell, with neighboring Eu2+ chains antiparallel. When Ln = Gd-Tm, ferromagnetically aligned Eu2+ ions interact with the Ln(3+) ions, which would overcome the magnetic frustration of triangularly aligned Ln(3+) ions and the EuLn(2)O(4) compounds show a simple antiferromagnetic behavior. (C) 2009 Elsevier Inc. All rights reserved.