Collapse of the f-band in CeNi with intermediate valence of Ce

Chem. Met. Alloys 4 (2011) 107-112

https://doi.org/10.30970/cma4.0172

Mykhaylo KOTERLYN, Bogdan MOROKHIVSKII, Roman YASNITSKII

On the basis of a narrow peaks (NP) model for the 4f‑derived density of states (DOS) near the Fermi energy proposed by us earlier, we present a detailed description of the temperature dependences of the contribution of Ce f‑states to the electrical resistivity, thermoelectric power, magnetic susceptibility, and electronic contribution to the specific heat for СеNi. It is shown that the dependences of the above mentioned characteristics in a wide temperature range are well described on the basis of a single narrow peak of Lorentzian shape, assuming temperature dependence of the peak parameters. At low temperatures (T < 20 K) the peak parameters are consistent with the corresponding parameters of the 4f DOS in the Anderson model for Kondo systems with strong orbital degeneracy of f‑states at the characteristic temperature T_K ≈ 330 K. At higher temperatures (T > 50 K) the best correspondence of the model to the experimental data was achieved considering a drastic reduction (collapse) by ~50 % of the width of the narrow peak for the DOS in a temperature range near T ≈ Θ_D = 115 K (Θ_D is the Debye temperature).

Temperature dependence of the contribution of Ce f‑states to the total electrical resistivity of CeNi (). The solid line shows the electrical resistivity calculated from Eq. 3. The inset shows the resistivity in the low-temperature region.

Keywords

Rare earth compounds / Electronic structure of metals and alloys / Electronic transport / Kondo effect