4f-Ligand dehybridization in the intermetallic compound series CeNi2(SnxSi1−x)2

Structural, transport, magnetic, and thermal measurements, as well as Ce-LIII spectroscopy were employed in this work in order to examine the 4f-ligand dehybridization in the series CeNi2(SnxSi1−x)2 (x=0, 0.2, 0.4, 0.6, 0.8, and 1.0). The results revealed that CeNi2Si2 is a typical intermediate-valence (IV) compound with strong s-f hybridization, while CeNi2Sn2 is a Kondo-lattice compound with a low Néel temperature TN∼1.9 K. With increasing x, the decrease of s-f hybridization will drive the series away from an IV regime toward a magnetically ordered state. From the results, the evolution arises from competitions between s-f hybridization, the Kondo scattering, and the RKKY interaction, as well as the crystal-field effect.