First-principles local-density formalism cluster-theory was used to determine the structure of Au-H and Ag-H complexes. The theory, plus empirical corrections, was then used to deduce donor and acceptor levels. The latter were compared with capacitance transient spectroscopic data. The results made it possible to determine the structure and electrical activity of such defects. Thus, the observed deep-level transient spectroscopy levels could be attributed to specific defects. The AuH3 and AgH3 defects had filled t2-manifolds which lay in the valence band and lacked donor activity. They possessed shallow 6s and 5s acceptor levels. Molecular hydrides of metal impurities were passive when inserted into voids or passivated multi-vacancy centers.

Calculations of electrical levels of deep centers A.Resende, R.Jones, S.Oberg, P.R.Briddon: Physical Review Letters, 1999, 82[10], 2111-4