An ab initio investigation was made of the microscopic structure of complexes in diamond involving interstitial Ni. The calculations were performed by using an all electron total energy methodology, based upon the full-potential approximation. The configurational symmetry, spin, formation and transition energies, electronic structure, and hyperfine parameters were computed for the active centers commonly found in synthetic diamond.

Band Gap States of Interstitial Nickel-Complexes in Diamond. R.Larico, J.F.Justo, W.V.M.Machado, L.V.C.Assali: Physica B, 2006, 376-377, 292-5