Ab Initio Studies of Fluorine Passivation on the Electronic Structure of the NV⁻ Defect in Nanodiamond

We have investigated using density functional theory the effect of fluorine termination of a (001) diamond surface on the electronic energy levels of an NV⁻ centre buried beneath the surface. We find that, like OH termination, fluorine passivates the surface and reduces the influence of the surface on the electronic properties of the NV⁻ centre. The results have significance for the optical properties of NV⁻ defects in nanodiamonds.