  Structural, electronic and thermodynamic properties of native defects in GaS
and GaSe monolayers are investigated by means of accurate ab-initio
calculations. Based on their charge transition levels we assess the influence
of the studied defects on the electrical properties of the monolayers.
Specifically, we show that native defects do not behave as shallow dopants and
their presence cannot account for the experimentally observed intrinsic doping.
In addition, we predict that native defects are efficient compensation and
recombination centers. Besides pointing out their detrimental nature, we also
calculate the corresponding finite temperature formation energies and provide a
window of growth conditions able to reduce the concentration of all relevant
native defects.
