  We discuss the side resonances of optically detected magnetic resonance in
diamond crystal and propose the new approach to the calculation of hyperfine
interaction in composed system, consisted of negatively charged
nitrogen-vacancy NV- center and nearby 13C nuclear spin. Energy levels and spin
states are obtained by new method. The base of this method is the using of
complete set of commuting operators. In zero magnetic field, predicted the
existence of metastable excited state.
