Deducing atomic models for point defects in diamond: The relevance of their mechanism of formation

There is often too little information about the properties of a point defect in diamond for one to be able to make an unambiguous assignment of an atomic model. One of the factors which is sometimes ignored in suggesting a complex atomic model is the route by which its constituents were assembled: the family tree of its generation. This general point is illustrated by considering some of the previously proposed multi-vacancy models for point defects (specifically EPR defects R7, R7a and R8) formed by annealing irradiated nominally defect-free diamond. As some of the inevitable precursors of the previously proposed models are not observed, alternative models are proposed.