A series of phenyl end-capped α-oligothiophenes containing four to seven thiophene subunits (4T–7T) was synthesized utilizing palladium-catalyzed cross-coupling reactions. UV/Vis spectroscopic analysis revealed one broad absorption band that shifts bathochromically with increasing number units. Structured emission spectra are observed Stokes shift ν~4000 cm−1 and quantum yields up 53%. End-capp...

In this paper we report on a combination of experimental and theoretical study of a new copolymer based on carbazole and methylthiophene (Cbz-Mth), in their neutral and oxidized states. We discuss the influence of chain length on conformational and optoelectronic properties with the DFT method. Conformational analysis shows that there are no big changes in the structural parameters of neutral o...

An analytical method of studying strong long-range electron–phonon and Coulomb interactions in complex lattices is presented. The method is applied to a perovskite layer with anisotropic coupling of holes to the vibrations of apical atoms. Depending on the relative strength of the polaronic shift Ep and the inter-site Coulomb repulsion Vc, the system is either a polaronic Fermi liquid, Vc > 1.2...

– Electrons coupled to local lattice deformations end up in selftrapped localized molecular states involving their binding into bipolarons when the coupling is stronger than a certain critical value. Below that value they exist as essentially itinerant electrons. We propose that the abrupt crossover between the two regimes can be described by resonant pairing similar to the Feshbach resonance i...

Over the last decade several competing models of high-temperature super-conductivity were proposed, most of them with short-range interactions. We review a more realistic model with strong on-site repulsive correlations, the Coulomb and strong finite-range electron-phonon interactions. Bipolarons in the model exist in the itinerant Bloch states at temperatures below about half of the characteri...

Electron-lattice interactions play a prominent role in quantum materials, making deeper understanding of direct routes to phonon-mediated high-transition-temperature ($T_{\mathrm{c}}$) superconductivity desirable. However, it has been known for decades that weak electron-phonon coupling gives rise low values $T_{\mathrm{c}}$, while strong leads lattice instability or formation bipolarons, gener...