Comparative high-resolution photoemission measurement was performed for ${\mathrm{CeB}}_6$ and ${\mathrm{CeCu}}_6$ to study the electronic structure near ${\mathit{E}}_{\mathit{F}}$. The photoemission spectra near ${\mathit{E}}_{\mathit{F}}$ of both compounds show a characteristic satellite at 270 meV from ${\mathit{E}}_{\mathit{F}}$ due to the spin-orbit splitting of a Ce 4f electron (4${\mathit{f}}_{7/2\mathrm{-}}$4${\mathit{f}}_{5/2}$), while the spectrum of ${\mathrm{CeB}}_6$ exhibits an additional small feature around 70 meV. Model calculations based on the noncrossing approximation show that this satellite is due to the crystal-field splitting (${\mathrm{\Gamma }}_{7\mathrm{-}}$${\mathrm{\Gamma }}_8$) of the Ce 4${\mathit{f}}_{5/2}$ state in ${\mathrm{CeB}}_6$.

• Received 6 July 1995

DOI:https://doi.org/10.1103/PhysRevB.52.9140