Structure of gold in silicon

Detailed information on the electronic structure of the neutral substitutional gold center in silicon (Au⁰) has been revealed from Zeeman studies of the donor and acceptor excitation spectra at 793 and 611 meV, respectively. The center is paramagnetic, S=1/2, with g_∥{}2.8 and g_⊥{}0, and has a static 〈100〉 tetragonal distortion. Reorientation between different equivalent distortions is observed even at 1.9 K which establishes the single substitutional nature for this gold center. The fact that g_⊥{}0 explains the failure to detect Au⁰ by EPR.