The carbon vacancy in diamond and many similar defects have strong electron

correlation giving rise to molecular multiplet structures. Sophisticated electron–

phonon interaction subsequently occurred at these defects giving rise to optical and

other effects associated with a dynamic Jahn-Teller interaction. Using ab initio

calculations the full vibrational spectrum of both the neutral and negatively

charged vacancy were obtained. Calculated local modes were consistent with

earlier interpretations of vacancy properties as based upon Group Theory.

Modification of the vibration spectra by a heavy metal – here nickel – was also

examined and implications for defect vacancy models briefly discussed.

Local Modes of Vibration at the Vacancy and Vacancy Models of Defects in

Diamond. J.E.Lowther: Computational Materials Science, 2009, 46[2], 520-3