A method is provided for producing phosphorescent emitter layers composed of at least one organic fluorescent emitter F and at least one metal complex K including organic complex ligands L and at least one heavy main group metal M selected from the group consisting of In, Tl, Sn, Pb, Sn and Bi. The organic fluorescent emitter F and the metal complex K may be individually deposited as layers on a substrate and subsequently reacted with each other, wherein the coordination sphere of the heavy main group metal M is changed by receiving the organic fluorescent emitter F.