Molecular dynamics of a low-band gap polymer, poly­{[4,8-bis­[(2-ethylhexyl)­oxy]­benzo­[1,2-b:4,5-b′]­dithiophene-2,6-diyl]­[3-fluoro-2-[(2-ethylhexyl)­carbonyl]­thieno­[3,4-b]­thiophenediyl]} (PTB7), and its 1:1.5 wt blend with a fullerene derivative, [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), accessible for organic photovoltaics was studied with the broadband dielectric spectroscopy (BDS) technique in a wide range of frequency (from 10–1 to 106 Hz) and temperature (from −130 to 150 °C). In the BDS spectra, three types of molecular mobility of the polymer chains designated as γ-, β1-, and β2-relaxations, along with conductivity and electrode polarization processes, were recognized, separated, and analyzed. The relaxation processes in PTB7 and PTB7:PC71BM were described with Arrhenius-type equations and related parameters were found. Their analysis allowed us to reveal the influence of the PC71BM molecules on the dynamics of the polymer chains. Based on dc conductivity data, the Cole–Cole diagrams for PTB7 and PTB7:PC71BM were plotted. They allowed for estimating the hole lifetime and its comparison with the hole extraction time.

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An efficient protocol was developed for the synthesis of π‐extended isocoumarins and polycyclic aromatic hydrocarbons based on the oxidative coupling of aromatic carboxylic acids with internal alkynes catalyzed by (cyclopentadienyl)rhodium complexes. The coupling chemoselectivity strongly depends on whether Cp or the methylated Cp* ligands are used. The pentamethyl derivative [Cp*RhCl2]2 predominantly gives isocoumarins, while the non‐methylated complex [CpRhI2]n produces naphthalene derivatives. The polyaromatic carboxylic acids (such as 1‐naphthoic acid, 1‐pyrenecarboxylic acid, fluorene‐1‐carboxylic acid, and dibenzofuran‐4‐carboxylic acid) are suitable for this approach. A mixture of Cp*H/RhCl3 can be used as a catalyst instead of [Cp*RhCl2]2. The structures of 3,4‐diphenylindeno[1,2‐h]isochromen‐1(11H)‐one and 7,10‐dimethyl‐8,9‐diphenylbenzo[pqr]tetraphene were determined by X‐ray diffraction. In addition, the optical properties of the prepared compounds were studied. 7,8‐Diphenyl‐10H‐phenaleno[1,9‐gh]isochromen‐10‐one was employed as an emissive layer for OLED manufacturing. The OLED emits yellow‐green light with a maximum intensity 1740 cd ⋅ m−2 at 15 V.

Studies on copper(II) tetrafluorenyl porphyrinate (CuTFP) and copper(II) tetraphenyl porphyrinate (CuTPP) have been focused on the charge carrier transport in their solid films and electroluminescence of their composites. In the dye layers deposited by resistive thermal evaporation, the mobilities of holes and electrons are on the order of 10 −5 and 10 −6 cm 2 V −1 s −1 for the charge transport under the influence of traps, and the charge mobility reaches the order of 10 −3 cm 2 V −1 s −1 at space-chargelimited current in the nontrapping mode. For the dye molecules, the correlation between the mobility of charge carriers and the distribution of the electron density on the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), which serve as hopping sites for holes and electrons, respectively, is considered. Organic light-emitting diodes incorporating the dye molecules as emitting dopants demonstrate electroluminescence in the near-infrared (IR) range.

The targeted design of lanthanide-based emitters for solution-processed OLEDs was aimed at the combination of high luminescence efficiency with solubility and charge carrier mobility.