Low-temperature study of the strongly correlated compound Ce ₃Rh₄Sn₁₃

Low-temperature results of the thermodynamic and transport properties of polycrystalline Ce₃Rh₄Sn₁₃ are presented. The study of the ground-state properties reveals that Kondo interactions become important below 2K, as evidenced by a large Sommerfeld coefficient and high magnetic resistivity. At 1K the specific heat exhibits a broad peak that is attributed to short-range magnetic order. Support is given by ac susceptibility measurements. The resistivity and the susceptibility around 80K are dominated by effects due to the crystal electric field splitting of the Ce³⁺ multiplet. Additionally, clear indications for local vibrations of Sn(2) atoms within the cage-like structure are deduced from an Einstein term in the specific heat. The crystal structure is known to form two atomic cages: one in which the Ce atoms are located; the other containing the Sn(2) atoms. Although strong correlations at low T are present in this system, the thermopower is found to be surprisingly small.