A theoretical investigation was made of the electronic and structural properties of substitutional and interstitial Ni impurities. The atomic structures, symmetries, acceptor and donor transition energies, and formation energies of isolated Ni were derived by using a total-energy all electron ab initio methodology. When compared with available experimental data on electrically and optically active centers in synthetic diamond, these results provided a new interpretation of the microscopic structures of the active centers.

An ab initio Investigation of Nickel Impurities in Diamond. R.Larico, J.F.Justo, W.V.M.Machado, L.V.C.Assali: Physica B, 2003, 340-342, 84-8