Polarized luminescence and absorption spectra of neutron-irradiated IaB type diamond have been measured in the 700 - 750 am spectral range. From these measurements the [111] orientation of electric dipoles for the 723.8 nm line has been concluded. Spectral hole burning (SHE) in the 723.8, 730.9, 731.7, 734.3 nm lines has been performed which alloys the analysis of the dynamics of the lattice defects.