We have investigated the contribution of Ce $4f$ states to the electronic structure of the intermetallic ferromagnet ${\mathrm{CePdIn}}_2$ by means of x-ray absorption spectroscopy and resonant and nonresonant photoemission spectroscopy. The line shape of the Ce $M_{5,4}$ absorption edge reveals the localized nature of the $4f$ states, and is consistent with a predominantly 3+ ionic state for Ce ions. Fitting of the Ce $3d$ core level gives a Ce $4f$ occupation number at room temperature of 0.92, which is in good agreement with the Ce effective magnetic moment of $2.20{\mu }_B$ (corresponding to $\sim 87\%$ of the free-electron moment) as calculated from the inverse magnetic susceptibility. Moreover, the hybridization strength between $4f$ and conduction electrons is found to be $\sim 180$ meV, revealing that ${\mathrm{CePdIn}}_2$ is a strongly hybridized system. This is consistent with the results from the analysis of the resonant valence band photoemission measurements at both the $N_{5,4}$ and the $M_5$ edges, showing that the Ce $4f$ states are composed of the features predicted by the single-impurity Anderson model, i.e., a broad $4f^0$ peak centered at 1.9 eV and two $4f^1$ spin-orbit states much closer to the Fermi level. The same spectra also show that the Ce $4f$ resonant spectral weight extends over a wide binding energy range, overlapping with that presumably occupied by the Pd $4d$ ligand states. This energy overlap is interpreted as a signature of the strong hybridization governing the system, which could possibly favor the emergence of long-range ferromagnetism through the indirect exchange between localized $4f$ states mediated by highly dispersive $d$ electrons.

• Received 9 September 2015
• Revised 16 November 2015

DOI:https://doi.org/10.1103/PhysRevB.92.235137