The interface of a zinc-terminated polar zinc oxide surface (0002) with a series of chemisorbed fluorinated benzylphosphonic acids has been studied using density functional theory. The calculations indicate that there is a substantial change in the binding energies and work function modification depending on the binding motif. The results also indicate that there is a pronounced difference in the magnitude and trends of the factors determining the total change in work function. The oxygen core-level binding shifts have been calculated and compared to available experimental data.