Valence fluctuations in YbNiAl4 compound

Abstract

Measurements of the magnetic susceptibility, electrical resistivity, and heat capacity are reported for the polycrystalline YbNiAl4 intermetallic compound. χ(T) has been measured up to 1000 K and its behavior is typical of a compound with the valence fluctuation between Yb3+ and Yb2+. This is especially evident from a broad maximum observed at 400 K and interpreted in frames of the interconfiguration fluctuation model. The Sommerfeld coefficient derived from the heat capacity measurements takes a small value of γ=16 mJ mol−1 K−2. The low temperature resistivity follows the AT2 dependence characteristic of a Fermi liquid.