Ultraviolet photoelectron spectra of Zn${\mathrm{F}}_2$ and Zn${\mathrm{Cl}}_2$

Energy distributions of photoelectrons from Zn${\mathrm{F}}_2$ and Zn${\mathrm{Cl}}_2$ films were measured in the photon energy range 10-27 eV. The photoelectron spectra show features that can be identified as the effect of crystal-field splitting in the Zn $3d$ levels in the final state. While the splitting in Zn${\mathrm{F}}_2$ appears to be obscured by the ${\mathrm{F}}^{-}$ $2p$-band peak, the doublet structure due to the crystal-field effect in Zn${\mathrm{Cl}}_2$ can be seen below the ${\mathrm{Cl}}^{-}$ $3p$-band spectrum. The crystal-field strength $10Dq$ in Zn${\mathrm{Cl}}_2$ as indicated by the splitting is found to be 3.1±0.2 eV.