Electroluminescence of several pyrazoloquinoline and quinoksaline derivatives

Experimental investigations of electrolumineseent spectra for several pyrazoloquinoline and quinoksaline derivatives have been performed. The investigations have shown that replacement of carbon by nitrogen in the middle aromatic rings and replacement of aromatic ring by methyl group shift the main spectral maxima from 404 up to 455 nm for photoluminescence and from 450 up to 560 nm for electroluminescence. Such wide range of the spectral shift of the luminescence and electroluminescence opens a possibility of using the materials like new electroluminophore. The experimental data show sufficient agreement with semi-empirical quantum-chemical calculations. The observed long-range wavelength spectral shift of the theoretically calculated and experimentally observed maxima is caused by electron-vibration shift. (c) 2006 Elsevier B.V. All rights reserved.