A study was made of H-related local vibrational modes at 2643, 2651, 2688, 2725, 2729 and 2775/cm. These were thought to arise from the C-H stretching modes of defects which were similar to the H-passivated C acceptor complex CAsH. These lines appeared in samples that had been grown by using trimethylgallium metalorganic precursors, and it was suggested that the 2688, 2725, 2729 and 2775/cm bands were due to CAs dimers that were decorated with one or more H atoms. The structures, energies and vibrational modes of (CAs)2, (CAs)2H and (CAs)2H2 complexes were deduced from first-principles local density functional cluster calculations.

J.P.Goss, R.Jones, S.Oberg, P.R.Briddon: Physical Review B, 1997, 55[23], 15576-80