The local vibrational modes of a weakly-bound C-H complex were identified by using infra-red absorption spectroscopy. After implanting protons at 20K, and annealing at 180K, two C modes at 596 and 661/cm and one H mode at 1885/cm were observed. The 3 modes originated from the same complex, which was identified as being a bond-centered H atom in the vicinity of a nearby substitutional C atom. First-principles theory was used to calculate the structure and local modes of C-H complexes, with H located at the first-, second- and third-nearest bond-center sites to substitutional C. The results supported this model.

Weakly Bound Carbon-Hydrogen Complex in Silicon. L.Hoffmann, E.V.Lavrov, B.Bech Nielsen, B.Hourahine, R.Jones, S.Oberg, P.R.Briddon: Physical Review B, 2000, 61[24], 16659-66