4f-Ligand dehybridization in the intermetallic compound series CeNi_2(Sn_xSi_(1-x))_2

摘要

Structural, transport, magnetic, and thermal measurements, as well as Ce-L_(III) spectroscopy were employed in this work in order to examine the 4f-ligand dehybridization in the series CeNi_2(Sn_xSi_(1-x))_2 (x=0, 0.2, 0.4, 0.6, 0.8, and 1.0). The results revealed that CeNi_2Si_2 is a typical intermediate-valence (IV) compound with strong s-f hybridization, while CeNi_2Sn_2 is a Kondo-lattice compound with a low Neel temperature T_N ～ 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.