Specific heat, electrical resistivity and thermoelectric power of YbNi4Si

The studies of the specific heat, electrical resistivity and thermoelectric power of YbNi4Si are reported. These studies are supported by magnetic susceptibility and X-ray photoemission spectroscopy (XPS) measurements. YbNi4Si does not order magnetically down to 4 K. Nearly in the whole temperature range studied the magnetic susceptibility follows a Curie law with μeff = 4.15 μB/f.u. This effective magnetic moment is close to the value expected for the 4f13 configuration (4.54 μB). The Yb2+ and Yb3+ peaks observed by XPS in the valence band region confirm the domination of the Yb3+ valence state. Based on the specific heat measurements, the electronic specific heat coefficient γ = 25 mJ/mol/K2 and the Debye temperature θD = 320 K were derived. A quadratic dependence of electrical resistivity at low temperatures has been observed. The Kadowaki–Woods ratio has been discussed. The thermoelectric power has been analyzed in the framework of the two band model.