A sharp line transition at 1.51385 eV has been observed in the photoluminescence spectra of an epitaxially grown crystal of GaAs. A Si3N4cap was applied by plasma deposition and the crystal was then annealed at 850 °C for 15 min. The sharp emission line was observed after annealing. This transition was analyzed in perturbing magnetic and strain fields and is shown to result from a donor‐acceptor‐type complex. Three additional sharp line transitions are reported and the behavior of all of these transitions is compared with the behavior of similar transitions reported in the literature. Models for the complexes involved are re‐examined and components of the complexes are suggested. All of the sharp line transitions were introduced in the growing process with the exception of the 1.51385‐eV line which was introduced in the capping and annealing process.