New easily functionalisable and highly fluorescent BOPAHY chromophores are synthesised via one pot two step reaction starting from commercially available pyrrole-2-carbaldehydes and respective acyl hydrazides in the presence of BF3·OEt2.

Absorption and emission spectra of 8-(4-dimethylaminophenyl)-1,3,5,7-tetramethyl-BODIPY have been calculated using Coupled Cluster (CC) approaches, Time-Dependent Density Functional Theory (TD-DFT) and a QM-informed MM approach. In the case of TD-DFT calculations solvent effects were included using the linear-response (LR), corrected linear response (cLR) and state specific (SS) Polarizable Continuum Model (PCM). We show that range-separated functionals give results in reasonable agreement with coupled cluster methods but both tend to overestimate excitation energies. Furthermore, we show that the SS-PCM approach is unable to provide a quantitative description of solvent effects in these systems, especially for the highly challenging charge-separated charge-transfer state. In contrast, the QM-informed MM approach gives results in good agreement with experiment and we propose a scheme which can be used to directly compare theoretically obtained spectra with experimental ones.

The temperature- and co-cation-dependent photoluminescence of zeolite confined Ag clusters was systematically investigated. Bright polychromatic emission and intriguing excited-state dynamics were observed and a kinetic model was proposed.

Water-soluble BOPAHY fluorophores have not yet been reported. The potential of 1,2,3-triazolium salts for the formation of water-soluble chromophores is explored. 1,2,3-Triazole-substituted pyrroles were synthesized in a metal-free pathway and alkylated to obtain water-soluble 1,2,3-triazolium BOPAHY dyes. High fluorescence quantum yields were observed for triazole-bridged BOPAHY dyes in DCM and moderate fluorescence quantum yields for 1,2,3-triazolium-bridged BOPAHY chromophores in DCM and water. The fluorescence of the freely rotatable 1,2,3-triazolium-linked BOPAHYs is partially quenched in water.

Only a few straightforward procedures for the preparation of indolo[2,3‐c]carbazoles are known, despite promising features for material applications. Herein we present a convenient synthesis of 5,10‐dihydrobenzo[a]indolo[2,3‐c]carbazoles using an oxidative cyclization of 1,2‐bis(1H‐indol‐2‐yl)benzenes prepared from readily accessible starting materials. Functionalization through electrophilic aromatic substitution reactions and palladium‐catalyzed cross‐coupling reactions were investigated, which lead to the isolation of new functionalized 5,10‐dihydrobenzo[a]indolo[2,3‐c]carbazoles, whose steady state electronic spectroscopy has been examined.

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The excited-state dynamics of four 5,10-dihydrobenzo­[a]­indolo­[2,3-c]­carbazoles in solution and in films were studied with stationary and time-resolved spectroscopies. The solvent dependency of the photophysics reveals no appreciable dipole moment in the ground state. In the excited state, electron-withdrawing substituents contribute to an outspoken charge-transfer character. In films, although the molecules are mostly present as monomers, the excited-state dynamics are characterized by a cascade of energy-transfer processes to excited dimers and aggregates which dominate the photoluminescence (PL) spectra. The properties of the aggregates depend on the used substituents. The electroluminescence spectra obtained from single-layer and multilayer devices mostly resemble the PL spectra, but show contributions from other species such as electromers or electroplexes. It is inferred that the different substituents lead to a different packing of the carbazole moieties, each of which has different mobilities and recombination probabilities.