The local vibrational mode absorption lines at 3079.2 and 983.3/cm, measured in semi-insulating LEC-grown GaAs, were due to the stretching and wagging mode of one H bonded to a light impurity atom. The investigation of GaAs grown without boric oxide encapsulant delivers arguments that this impurity atom was N in the N-vacancy (NAs-VGa) defect, which was responsible for the vibrational quadruplet line at 638/cm.

The Nitrogen-Hydrogen-Vacancy Complex in GaAs. W.Ulrici, F.M.Kiessling, P.Rudolph: Physica Status Solidi B, 2004, 241[6], 1281-5