Abstract: The electronic structure and optical properties of pure, C-doped, C–F codoped and C–F–Be cluster-doped ZnO with a wurtzite structure were calculated by using the density functional theory with the plane-wave ultrasoft pseudopotentials method. The results indicate that p-type ZnO can be obtained by C incorporation, and the energy level of C_{m O} above the valence band maximum is 0.36 eV. The ionization energy of the complex Zn₁₆O₁₄CF and Zn₁₅BeO₁₄CF can be reduced to 0.23 and 0.21 eV, individually. These results suggest that the defect complex of Zn₁₅BeO₁₄CF is a better candidate for p-type ZnO. To make the optical properties clear, we investigated the imaginary part of the complex dielectric function of undoped and C–F–Be doped ZnO. We found that there is strong absorption in the energy region lower than 2.7 eV for the C–F–Be doped system compared to pure ZnO.

Key words: first-principles, electronic structures, optical properties, wurtzite ZnO