Ruddlesden-Popper compounds are a class of materials with a special layered structure that makes them interesting for numerous applications—as superconductors or catalysts, for example, or for use in photovoltaics. There have been many halides and oxides of this structural type before now, but no nitrides. Although scientists expected Ruddlesden-Popper nitrides to have outstanding material properties, they were unable to actually manufacture them.
