High-resistivity samples were implanted with H and D to a dose of 5 x 1015/cm2. After heat treatment (380 to 540C, 1200s), several electron paramagnetic resonance spectra could be detected upon illumination. The most prominent ones were Si-B3, which was attributed to the split self-interstitial, and a new spectrum, labelled Si-NL51. On the basis of its angular dependence, this center was suggested to arise from the S = 1 excited neutral charge state of a <100>-oriented complex with a tetragonal g tensor (g|| = 2.00707, g = 2.00069) and crystal field interaction (19MHz).

P.Stallinga, T.Gregorkiewicz, C.A.J.Ammerlaan, J.V.Gorelkinskii: Solid State Communications, 1994, 90[6], 401-4