Highly efficient orange OLEDs with narrow-emitting symmetric tetradentate platinum( ii ) complexes based on rigid steric hindrance aza-triptycene pyridazine ligands

The introduction of an aza-triptycene unit with a Y-shaped rigid 3D molecular structure into tetradentate platinum( ii ) complexes helps to realize narrow-emitting and highly efficient OLEDs even at high doping concentrations.