A Resende1, J Goss1, P R Briddon2, S Öberg3 and R Jones1
Spin-polarised  local   density functional cluster   calculations  are
carried  out   on substitutional  Au and  Au-H 
    complexes in Si.
Slater's transition  argument  and  Janak's  theorem are  combined  to
discuss the donor-acceptor  levels of the  defects and the results are
compared with experiment.  The calculations give a good account of the
donor/acceptor levels of Au and the Au-H pair.  They confirm that the
G1, G2 and G4 levels are due to Au-H.  Au-H 
  is found to be an
electrically inactive  defect and may  be identified with  the passive
defect found experimentally.