A novel method to predict the solid-state ab-initio photoluminescence spectrum of defects in crystals has been created

Our method works for defects with the same symmetry in ground and excited state, which could not necessarily be treated by existing methods.

This is accomplished by using a cluster calculation with TD-DFT and applying a low frequency cutoff to recreate the solid-state.

The low frequency cutoff is shown to eliminate vibrational modes unique to the surface of the cluster, and demonstrates a connection between cluster and solid-state.

Furthermore, our cluster calculation demonstrates the first vibrationally resolved ab-initio photoluminescence spectrum of NV- centres in nanodiamonds.

Our method has been recently published in Journal of Applied Physics.