In many cases, several distinct electronic structures are found within a small energy window. These highly complex electronic structures would ideally be treated with multiconfigurational approaches, which is however outside the scope of studies that aim to understand the catalytic behaviour of singleatom catalysts. In terms of assignments to the experimentally observed Mössbauer signatures, we emphasize that unpaired electrons in the graphene environment do not lead to different isomer shift or quadrupole splitting values. Nevertheless, we expect that such electronic structure details can be important for catalysis, as was recently suggested for a hydrogen evolution catalysis with molecular porphyrin complexes .