Electroluminescence of a Zinc Complex Exciplex with a Hole-Transporting Material

Russian Physics Journal - Results of theoretical and experimental studies of exciplex of a zinc complex Zn(DFP-SAMQ)2 with the hole-transporting layer of NPD are presented. It is shown that at...     

Evolution of Surface Morphology of Anthracene Single Crystals Under Annealing

Russian Physics Journal - In this work, the effect of formation of macrosteps under dissolution of the anthracene single crystal surface is shown for the first time. Under standard conditions (room...     

Vibronic Spectra of Bifluorene and Terfluorene

Russian Physics Journal - Using the method of the density functional theory (DFT/B3LYP/6-31G(d,p)), the vibrational absorption and emission spectra of bifluorene and terfluorene molecules are...     

Luminescence of Zn<Subscript>2</Subscript>L<Subscript>2</Subscript>- and PVC-based organic molecular compositions under photo- and electroexcitation

Spectral and luminescent properties of Zn₂L₂ complex {mu-2-bis((3-pyridine-2-il)-5-(2-salicyldeniminophenyl)-1,2,4-triaurum(2-))dizinc(2+)solvate with ethanol} are investigated in solutions, powder, and thin polyvinylcarbazole (PVC) films. The trends in their change versus the nature, aggregate state, and excitation method are established. Electroluminescence (λ_max = 493 nm) of an ITO/PEDOT/PVC: Zn₂L₂/LiF/CaMg/Ag device is excited, and its current-voltage and brightness-voltage characteristics are investigated.     

Spectral-Luminescent and Electroluminescent Properties of Charge-transfer Systems Based On Electron-donating Diphenylamine Derivatives and Acceptors of Dibenzothiophene Sulfone and Phenanthridine

Spectral characteristics and luminescence under the photo- and electro-excitation of substituted dibenzthiophene sulfone and phenanthridine were studied in this paper. Diphenylamines are substituents introduced in the 2nd and 7th positions (linear configuration) or the 3rd and 6th positions (angular configuration) of dibenzthiophene sulfone or phenanthridine. All molecules show delayed fluorescence, both in solutions and films produced by thermal vacuum deposition. The value of the energy gap between the S₁ and T₁ states has been estimated and is shown to depend not only on the spatial arrangement of the fragments among themselves (linear or angular), but also on the nature of the substituent in diphenylamine. The highest electroluminescence brightness was found for the molecules, in which triplet levels are involved, both through the process of triplet–triplet annihilation and through thermally activated delayed fluorescence.

     

Luminescence of metal complexes of chelate-substituted tetraphenylporphyrin

The luminescence and absorption spectra of some metal complexes of new tetraphenylporphyrin derivatives containing a chelating group with a heavy atom in the ligand structure were studied and compared with the properties of the zinc complex of unsubstituted tetraphenylporphyrin. The quantum yields of fluorescence and phosphorescence of liquid and frozen solutions of these compounds were measured. The life-times of delayed emission have been estimated, and the nature of bands in the absorption and luminescence spectra of the complexes and their relation with the structure are discussed.     

Inkjet Printing of Organic Light-Emitting Diodes Based on Alcohol-Soluble Polyfluorenes

Russian Physics Journal - Ink compositions for inkjet printing based on poly(9.9-dioctylfluorene) and its alcohol-soluble analog are created. Current–voltage, brightness–voltage, and...