Experimental and theoretical study of the effect of the substituent nature on the luminescent properties of scandium complexes with substituted 8-hydroxyquinolines

The luminescent properties of homoleptic scandium complexes with 2-substituted 8-hydroquinolines bearing the substituent groups H (1), CH3 (2), CN (3), and NH2 (4) were studied for use as emission layers in organic light-emitting diodes. It was found that the introduction of a substituent into the 2-position makes its possible to effectively shift the emission maximum to the blue or red region: to 530 nm (yellow-green) by 1 and 2, 615 nm (orange) by 3, and 495 nm (blue-green) by 4. The structure and the optical properties of the complexes were determined by density-functional-theory quantum-chemical calculations. The theoretical spectra agree well with the experimental photoluminescence spectra.