Magnetic anomalies and spin-glass-like behavior in Ce ₂CuGe ₆

A Ce-based intermetallic compound Ce ₂CuGe ₆ and its La analogue La ₂CuGe ₆ were synthesized and examined by X-ray powder diffraction, electrical resistivity, magnetic susceptibility, X-ray absorption spectrum and specific-heat measurements. The results reveal that Ce ₂CuGe ₆ is an antiferromagnetic Kondo-lattice compound with T _N 15 K. The effective moment deduced from paramagnetic region is 2.58 μ _B per cerium ion, which is close to localized Ce ³⁺ free ion in ²F _5/2 state. X-ray absorption measurement also precluded the existence of an intermediate valence state. The magnetic entropy calculated from heat capacity specific-heat measurement suggested a doublet ground state. In addition, we also observed a spin-glass-like behavior in this material. The spin-glass-like behavior might be due to the complex interplay between magnetic interactions.