Photoluminescent properties of novel design heteroleptic Zn(II) complexes.

Three novel heteroleptic Zn(II) complexes containing 8-hydroxy quinoline and various pyrazolone-based derivatives were synthesized and their structures confirmed by 1 H-nuclear magnetic resonance, mass spectrometry, Fourier transform infra-red spectroscopy, UV-vis analysis and element analysis. All three complexes showed good photoluminescence properties in the solid state and in solution in the maximum emission range from 475 to 490 nm with a quantum yield of 0.45 to 0.51. Absorption spectra revealed that the complexes possessed a maximum absorption range of 272-281 nm with a band gap of 2.59-2.68 eV. The highest occupied molecular orbital and lowest unoccupied molecular orbital of all the complexes were determine by cyclic voltammetry. All complexes displayed high thermal stability. These characteristics were assessed to find suitability for an alternative cheap light emitter for organic light-emitting diodes.