1. Different defects in Diamond have different phonon spectra.

  2. A new way to calculate these and a comprehensive investigation of the phonon spectra of different defects in diamond was carried out by I. Rosenblum, S. Brandon and JA.

  3. These results have been compared with experimental samples treated by different irradiation processes in collaboration with Steve Prawer of U. Melbourne in Australia.

  4. By comparing peaks of phonon spectra with peaks of Raman spectra we can deduce which defects are present in the experimental samples. (Raman spectroscopy = laser interacts with phonons - laser photons are shifted.)