Photoelectron-spectroscopy studies of Ce${\mathrm{Al}}_2$, La${\mathrm{Al}}_2$, and the "chemically compressed" alloys ${\mathrm{Ce}}_{0.6}$${\mathrm{Y}}_{0.4}$${\mathrm{Al}}_2$ and ${\mathrm{Ce}}_{0.6}$${\mathrm{Sc}}_{0.4}$${\mathrm{Al}}_2$ were performed with use of synchrotron radiation. For all compounds the $4f$ binding energy is 2.55 ± 0.1 eV. These results, combined with previous bulk-property results, motivate a reevaluation of Anderson-model parameters and mechanisms as applied to Ce${\mathrm{Al}}_2$.

• Received 18 December 1980

DOI:https://doi.org/10.1103/PhysRevLett.46.1104