Electronic structure and thermodynamic properties of CeRh(2)Sn(4) and LaRh(2)Sn(4).

The electronic structure and thermodynamic properties of CeRh(2)Sn(4) and LaRh(2)Sn(4) are reported. The crystal structure of CeRh(2)Sn(4) has been determined from single-crystal diffraction experiments. The Ce core-level x-ray photoemission spectra and Ce L(III) x-ray absorption data unanimously indicate a stable trivalent state of the Ce ions in CeRh(2)Sn(4), consistent with static magnetic susceptibility. Thermodynamic measurements for CeRh(2)Sn(4) show a noncollinear antiferromagnetic ordering with a ferromagnetic component at T(N)≈3.2 K. There is evidence for spin fluctuations in both CeRh(2)Sn(4) and LaRh(2)Sn(4). A Fermi surface analysis reveals sections, which could generate 'nesting' instabilities and be responsible for the spin fluctuation effects. Both CeRh(2)Sn(4) and LaRh(2)Sn(4) exhibit slight homogeneity ranges and can be described by RE(1+x)Rh(2)Sn(4-x), where [Formula: see text] for Ce and [Formula: see text] in the case of La. Implantation of additional Ce atoms into the CeRh(2)Sn(4) structure leads to a distinct lowering of T(N) and the weakening of the ferromagnetic component of the magnetic ground state, whereas for the La-based systems the alloying reduces the strong diamagnetism.