The electronic structure of pure BaF2 crystal and La doped BaF2 crystal have been calculated using a self-consistent molecular-cluster model. The cluster is embedded in the crystal lattice and the entire system is treated iteratively in the Hartree-Fock-Slater local-density theory. As La doped BaF2 is concerned

the obtained results reveal that the Fi introduced by La may contribute to the suppression of the slow component in the scintillation light of BaF2 crystal.