The nitrogen-vacancy center in diamond re-visited
  Symmetry considerations are used in presenting a model of the electronic structure and the associated dynamics of the nitrogen-vacancy center in diamond. The model accounts for the occurrence of optically induced spin polarization, for the change of emission level with spin polarization and for new measurements of transient emission. The rate constants given are in variance to those reported previously. 
N. B. Manson, J. P. Harrison and M.J. Sellars (Australian National   University)