Luminescent complexes beyond the platinum group: the d10 avenue

Luminescent metal complexes are key materials for several applications such as lighting, analytical probes, and lasers. In many cases compounds based on precious (i.e. platinum group) and rare earth metals are utilized, which are often rather expensive and environmentally problematic. In recent years, interest is growing in luminescent complexes based on less traditional but more abundant and cheaper metal elements. In this scenario compounds of metals with a d10 electronic configuration are playing a prominent role, also thanks to the versatility of their luminescent levels which can be of ligand centred, charge transfer or, in the case of polynuclear compounds, even metal-centred nature. Here we focus on some selected examples of Cu(I), Ag(I), Au(I), Zn(II) and Cd(II) luminescent complexes to suggest some possible routes towards promising and unprecedented emitting materials.