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Electrochemiluminescence (ECL), a light-emitting phenomenon induced by electrochemical redox reactions, has the potential for applications in lightweight and flexible light-emitting devices. Previously, an ultrafast ECL response below 100 μs was successfully obtained under an applied AC voltage by introducing Ru(bpy)32+, an orange ECL material, onto a DNA-modified electrode. This study introduced blue-luminescent 9,10-diphenylanthracene (DPA) into an ECL device consisting of the DNA/Ru(bpy)32+ hybrid electrodes. Consequently, blue ECL from DPA was obtained from the DNA/Ru(bpy)32+ hybrid electrode at a lower applied voltage than that required to induce the redox reactions of DPA itself. This lower-voltage-drivable blue ECL was attributed to triplet–triplet energy transfer from Ru(bpy)32+ in the DNA/Ru(bpy)32+ hybrid electrode followed by a triplet–triplet annihilation upconversion reaction of DPA in the electrolyte solution. Moreover, ultrafast-response, electrochemically triggered blue luminescence from DPA was successfully observed.

Molecules comprising several ferrocene residues constitute an intriguing group of compounds for various applications. Here, the total synthesis of a new example of a ferrocene-containing dendrimer is presented. The target compound was obtained in excellent combined yield (65%) employing facile, chromatography-free methods at each step. Interesting findings, meeting the dynamic covalent chemistry concept, are reported. Cyclic voltammetry analyses revealed one pair of current signals for the ferrocene moieties. Ultimately, the synthesized ferrocene-containing dendrimer has been used as an innovative recognition material for 9,10-diphenylanthracene, a polycyclic aromatic hydrocarbon, with the limit of detection value equal to 0.06 μM.

Thermolytic reactions of 9,10-diphenylanthracene endoperoxide (1) and its derivatives having deuterated phenyl groups and phenyl groups with fluorinated substituents were investigated as chemilumin...

9,10-Diphenylanthracene cubic nanoparticles (DPA CNPs) with aggregation-induced emission characteristic (AIEgens) were synthesized through a facile reprecipitation method; then, a bright and stable...

A set of anthracene containing polyfluorenes (PFs) having 9,10-diphenylanthracene with alkyl substituents and aniline containing fluorenes were prepared. Commonly, light-emitting polymers were synthesized using expensive palladium-like catalysts. In the present work, palladium was replaced by copper as a cost-effective PF synthesis catalyst, which is also suitable for large-scale polymer synthesis. Synthesized PFs emit light in the blue region with a bandgap of 2.87–2.90 eV. Thermally stable PFs had a decomposition temperature of more than 305°C and a glass transition temperature of 125–138°C. PFs were soluble in organic solvents and had a molecular weight of around 21,700–25,500. The electrochemical study of these PFs showed low level of highest occupied molecular orbital (HOMO) energy of −5.16 to −5.26 eV, which was significantly higher than that of PF (5.7 eV). These findings suggested that the resulting PFs could be used as a component of the light-emitting diode.

Improving the efficiency of triplet fusion upconversion (TF-UC) in the solid-state is still challenging due to the aggregation and phase separation of chromophores. In this work, two 9,10-diphenylanthracene (DPA) derivatives based on the modification of the 9,10-phenyl rings with bulky isopropyl groups (bDPA-1 and bDPA-2) were used as emitters. By using platinum octaethylporphyrin (PtOEP) as the sensitizer, TF-UC performance was comprehensively investigated in 3 media: toluene solution, polyurethane thin film and nano/micro-crystals in a polyvinyl alcohol matrix. Only a small difference in upconversion efficiency between the bulky DPAs and the DPA reference was observed in toluene solution and polyurethane thin film. However, a large improvement of TF-UC quantum yield was achieved in bDPA-2/PtOEP crystals (ΦUC = (0.92 ± 0.05)%) with a low excitation intensity threshold (52 mW cm-2) compared to that of DPA/PtOEP crystals (ΦUC = (0.09 ± 0.03)%). This difference was largely attributed to improved dispersibility of the PtOEP sensitizer in the bDPA-2 emitter crystals. The bulky DPAs also show excellent stability under UV irradiation with exposure to oxygen compared to DPA. These results provide a strategy for developing efficient solid-state TF-UC systems based on nano/micro-particles of emitter-sensitizer mixtures.

Fine tuning of the structures and properties of hydrogen-bonded organic frameworks (HOFs) has been considered to be a huge challenge. Herein, we reported the controlled synthesis of meso-tetrakis(c...

In this work, 9,10-diphenylanthracene (DPA) crystals in centimeter size were grown by melt as well as solution methods. The optical properties of both crystals were investigated using X-ray stimula...

In this work a new strategy for selective heterogeneous electrochemiluminescent detection of representative members of polycyclic aromatic hydrocarbons (PAHs), namely rubrene and 9,10-diphenylanthracene is introduced. This strategy is based on a suitable selection of a co-reactant in order to meet the thermodynamic requirements necessary for emission of electrochemiluminescence by abovementioned analytes, which are immobilized on the electrode. Further rational choose of coreactant (i.e., benzoyl peroxide, persulfate, tripropylamine, tetraphenylborate) could lead to selective quantification of target PAH among many other PAHs in detection mixture. The method can be useful for distinguishing PAHs in environmental monitoring and clinical assays assuming different level of their cancerogenity.

The work describes the development of a new electrochemiluminescent (ECL) transducer based on 9,10-diphenylanthracene (DPA) / polyvinyl butyral / glassy carbon film modified electrode along with the design and manufacture of a low-cost spin-coating system based on Arduino Atmega 2560, which was used to create the abovementioned transducer. It was proved that the performance of this spin coater is comparable to common commercial models, but with much lower total cost of the device. The appearance of ECL from DPA molecules of the transducer in reaction with a relatively new ECL co-reactant tetraphenylborate (TPB) in aqueous solution has demonstrated the applicability of spin-coating technique for creation of new types of ECL transducers. Application of such transducers allows full use of the unique properties of TPB co-reactant and eliminates a problem of formation of TPB based precipitates, which occurs when such common fluorophore as Ru(bpy)32+ is utilized.

The electrochemiluminescence (ECL) properties of polycyclic aromatic hydrocarbons (PAHs) are excellent on account of the high photoluminescence quantum yield. However, the poor solubility and radical instability of PAHs in the aqueous solution severely restricted further biological application. Here 9,10-diphenylanthracene (DPA) nanoblocks (NBs) with good dispersibility and stability in aqueous solution were prepared according to morphology-controlled technology employing water-soluble polymers as a protectant. Furthermore, an ECL “off–on” switch biosensor was developed based on a novel ECL ternary system with DPA NBs as luminophore, dissolved O2 as coreactant, and Pt–Ag alloy nanoflowers as the coreaction accelerator, which achieved a high-intense initial ECL signal. Subsequently, the Fc-DNA as ECL signal quencher was assembled on the electrode surface to quench the initial ECL signal for a “signal-off” state. Meanwhile, DNA swing arm was modified on the electrode surface for one-step DNA walker amplific...

The molecular and crystal structure of perfluoro-9,10-diphenylanthracene and its perfluorinated dihydro derivatives (9,10-diphenyl-1,4-dihydroanthracene, 9,10-diphenyl-2,9-dihydroanthracene, and cis,trans- 9,10-diphenyl-9,10-dihydroanthracenes) is determined by single crystal X-ray diffraction. 9,10-Diphenyl- 2,9-dihydroanthracene is analyzed in cocrystal with 9,10-diphenyl-1,4-dihydroanthracene (2:1). It is shown that in the studied compounds the angles between the planes of the phenyl rings and the anthracene core are close to 90°. According to the DFT/B3LYP/6-31G(d) calculations, 9,10-diphenyl-1,4-dihydroanthracene is most thermodynamically stable among the studied dihydroanthracenes. There are C–F…π interactions and no π-stacking interactions in the crystals of the studied compounds.

It has been hypothesized that alkyl chains are inactive for electron transport processes through the chains. However, our theoretical study unveiled that loop-like alkyl chains can accelerate the e...

Efficient organic light-emitting diodes (OLEDs) can be obtained using multilayered architectures where the processes of charge injection, transport and recombination are separated and optimized in each layer. Processing these structures from solution requires strategies to avoid redissolution or damage of the previously deposited layers. Several reports have demonstrated the development of cross-linkable hole transport materials, while less literature describes the synthesis and applications of such wide bandgap host materials for multilayered OLEDs. In this work we introduce a cross-linkable derivative of 9-(4-(10-phenylanthracene-9-yl)phenyl)-9H-carbazole incorporating styrene moieties (SPhPC) which can be efficiently cross-linked via radical polymerization. We present the synthesis and characterization of SPhPC, as well as its application as the host in the light-emitting layer to prove the concept of solution processed blue OLEDs.

To increase the practical usefulness of solid-state sensitized upconversion (UC) materials as components of solar energy harvesting systems, it is important to identify and suppress loss mechanisms, and increase the UC quantum yield (ΦUC). Here we focus on a benchmark UC system consisting of the emitter 9,10-diphenylanthracene (DPA) and the sensitizer platinum octaethylporphyrin (PtOEP) in a rigid poly(methyl methacrylate) (PMMA) matrix, and show that one of the major losses originates from Förster resonant energy transfer (FRET) from DPA back to PtOEP. Even though DPA emission lies within the PtOEP transparency window, the quantitative assessment of singlet exciton diffusion for samples with a high DPA content evidences that long-range FRET results in effective exciton trapping by PtOEP. A dramatic factor-of-6 reduction of the DPA emission quantum yield occurs even at PtOEP concentrations as low as 0.05 wt%. To alleviate this problem, we demonstrate a new concept based on the introduction of highly emissive sink sites to trap the singlet excitons produced upon annihilation prior to their quenching by the sensitizer. For DPA/PtOEP blends in PMMA, 1,6-bis-[2,5-di(dodecyloxyphenyl)ethynyl]pyrene is shown to be a useful sink, which results in 1.5-fold increase of the ΦUC. A maximum ΦUC of 2.7% was achieved, which is among the highest reported values for rigid sensitized UC polymers.

Triplet–triplet annihilation (TTA) is an attractive way to boost the efficiency of conventional fluorescent organic light-emitting diodes (OLEDs). TTA-active anthracene derivatives are often considered as state-of-the-art emitters due to the proper energy level alignment. In this work, TTA properties of a series of highly fluorescent nonsymmetrical anthracene compounds bearing 9-(4-arylphenyl) moiety and 10-(4-hexylphenyl) fragments were assessed. Two different methods to enhance the TTA efficiency are demonstrated. First, the intensity of TTA-based delayed fluorescence directly depended on the intersystem crossing (ISC) rate. This ISC rate can be significantly enhanced in more conjugated compounds due to the resonant alignment of S1 and T2 energy levels. While enhanced ISC rate slightly quenches the intensity of prompt fluorescence, the rise of the triplet population boosts the intensity of resultant delayed fluorescence. Second, the triplet annihilation rate can be significantly enhanced by optimization...

In order to develop blue emitters in organic light-emitting diodes (OLEDs), we synthesized two materials, 9-(9,10-diphenylanthracen-6-yl)-9H-carbazole and 1-(9,10-diphenylanthracen-6-yl)-1H-indole by Buchwald–Hartwig reactions. To investigate their electroluminescent performances, multilayer devices were fabricated by following structure: indium-tin-oxide (ITO) (180 nm) / N,N'-di(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (NPB) (50 nm) / blue emitters (30 nm) / 4,7-diphenyl-1,10-phenanthroline (Bphen) (30 nm) / lithium quinolate (Liq):Al (100 nm). A device using 1-(9,10-diphenylanthracen-6-yl)-1H-indole exhibited an efficient blue emission with luminous, power, and external quantum efficiency of 3.11 cd/A, 1.60 lm/W, and 2.82% at 20 mA/cm2, respectively and CIE (x, y) coordinates of (0.15, 0.13) at 6.0 V.

Two new contorted polycyclic aromatic hydrocarbons (PAHs) 1 and 2 have been synthesized by Perepichka and coworkers (Org. Lett., 2015, 17, 4224). In this work, we aim to clarify the effect of packings of the isomers on the charge-transfer mobility of PAHs by quantum chemistry calculations combined with the Marcus–Hush electron transfer theory. The isomers reveal dissimilar properties with PAH2 having a much smaller energy gap than PAH1. Significantly, the maximum hole mobility of PAH2 is nearly 3.5 times larger than that of PAH1, while the adiabatic ionization potential (IP) value of PAH2 is smaller than that of PAH1. In the solid state, PAH2 packs in a unique two-dimensional herringbone motif with high intrinsic hole mobility and suitable adiabatic ionization potential (IP) values making it a good p-type material.

The low cost, ease of preparation, colour tunability and wide application range garnered huge research interest on organic light emitting diode materials (OLED). The development of white light-emitting organic diode materials is mostly targeted for this. Anthracene derivatives have recently emerged as low-cost and efficient blue light-emitting diodes. However, developing efficient organic diode materials that cover the entire visible spectrum is very challenging. Herein, we demonstrated that Nile red (NR)-doped 9,10-diphenylanthracene (DPA) nanoaggregates provided strong white light emission upon excitation with near UV light. The dual emissions of the DPA nanoaggregates covering the blue and green regions were exploited and combined with the controlled red emission of the properly doped NR dye to cover the full visible spectrum, rendering white light emission with a quantum yield of >0.4. The fluorescence spectra of the DPA nanoaggregates doped with NR at various concentrations were monitored and their CIE coordinates were followed to evaluate the proper doping ratio for equal-energy white-light emission. Concurrent time-resolved emission studies provided mechanistic insights into the energy transfer from the exciton and excimer states of DPA to NR. It was revealed that the energy transfer from the singlet excitonic state of DPA followed the diffusion-assisted resonance energy transfer (RET) model. On the other hand, the excimer state showed negligible diffusion and energy transfer from this state found to follow the single-step Forster resonance energy transfer mechanism. The observation of efficient white light emission in the doped DPA nanoaggregates was proposed to have prospective applications in OLED devices, given the fact that triplet excitons may be exploited for emission through the efficient triplet–triplet annihilation contribution to fluorescence enhancement.

Anthracene and its derivatives are organic semiconducting materials that have prospective applications in organic solar cells and organic light emitting diodes. A thorough understanding of the photophysics and exciton dynamics is imperative for the effective utilization of these materials in optoelectronics. Herein, we have presented the exciton dynamics of a highly emissive anthracene derivative, namely, 9,10-diphenylanthracene (DPA) in nanoaggregate, thin film and crystalline forms. In contrast to the strong blue molecular emission in solution, DPA in the solid form exhibits emission from both the exciton and excimer state, covering the blue and green spectral region. In the well-ordered crystalline state, excimer emission dominates, while in the nanoaggregate form, the relative contribution of the excimer state decreases with the decrease in the size of the nanoparticle. In crystals, thin films and larger size nanoaggregates, favourable intermolecular orbital overlap by the adjacent phenyl substituents of DPA in the dominant α-phase packing allows for the fast relaxation of the exciton to excimer state in a sub-nanosecond timescale, as measured by time-resolved emission studies. Prior to trapping in the excimer state, the diffusion of singlet excitons has been revealed via the exciton–exciton annihilation kinetics measured by the excitation fluence dependent ultrafast emission decay. The singlet exciton diffusion coefficient in the DPA nanoaggregate is noted to be almost an order of magnitude slower than that in the anthracene nanoaggregate previously reported. The near perpendicular orientation of the two phenyl rings at the 9 and 10 position of anthracene causes an elongation in the intermolecular distance of the anthracene cores, which impedes the exciton diffusion rate. However, the ordered molecular packing of the DPA molecules in the thin film and crystal facilitates significantly faster singlet exciton diffusion.

A series of tetraphenylethene 9,10-diphenylanthracene (TPE-DPA) derivatives have been synthesized, and their photophysical properties studied. Photoluminescence measurements in PMMA, neat films and nanoparticle dispersions reveal that different aggregation states are formed, which leads to different photophysical behavior. The triplet excited state properties were studied using Pt(II) octaethylporphyrin (PtOEP) as triplet sensitizer. Upconverted emission from the DPA moiety is observed in nanoparticle dispersions of each derivative. A higher upconverted emission intensity is observed in aerated (compared to deaerated) solutions of the derivatives following irradiation, which is attributed to oxidation of the TPE moiety. These results provide valuable insight for the design of AIE luminogens for triplet-triplet annihilation upconversion (TTA-UC).

An important challenge when developing materials for triplet–triplet annihilation upconversion (TTA-UC) is achieving efficient and well-functioning solid-state systems. We here explore the effect of intramolecular TTA in oligomers and dendrimers based on the 9,10-diphenylanthracene (DPA) chromophore. The macromolecules are sensitized using palladium porphyrin, both in solution and in solid poly(methyl methacrylate) (PMMA), demonstrating a positive effect on overall upconversion in the solid state correlating with the well-controlled size of the DPA constructs. The UC kinetics is modeled and fit to steady-state and time-resolved emission data to give further insight into the intramolecular excited-state migration and annihilation in the macromolecular annihilator systems.

This paper reports synthesis and electroluminescent properties of the tert -butylated arylamine-substituted 9,10-diphenylanthracene derivatives for organic light-emitting diodes. The devices using these materials were fabricated in the following sequence: indium-tin-oxide/ N , N' -di(1-naphthyl)- N , N' -diphenyl-(1,1′-biphenyl)-4,4′-diamine/emitting material/bathophenanthroline/lithium quinolate/aluminum. All devices showed the efficient electroluminescence depending on the photoluminescent properties of emitters. In particular, a device using 2- tert -butyl-9-(9,10-diphenylanthracen-2-yl)-9 H -carbazole exhibited blue emission with the maximum luminance, luminous efficiency, power efficiency and external quantum efficiency of 2552 cd/m 2 , 2.14 cd/A, 1.17 lm/W and 2.04% at 20 mA/cm 2 , respectively, and Commission Internationale d′Eclairage (CIE) coordinates of (0.15, 0.12) at 6.0 V. These results suggest that the degree of self-aggregation of the emitters and charge-balances in the emitting layers of devices would be important roles in electroluminescent properties of devices.

By incorporating different number of pyridine rings to the periphery of the 9,10-diphenylanthracene (DPA) core, four new pyridine-containing DPA derivatives, 3-(4-(10-phenylanthracen-9-yl)phenyl)pyridine ( AnPy ), 9,10-bis(4-(pyridin-3-yl)phenyl)anthracene ( AnDPy ), 3,3'-((2-(pyridin-3-yl)anthracene-9,10-diyl)bis(4,1-phenylene))dipyridine ( AnTPy ), 3,3'-(9,10-bis(4-(pyridin-3-yl)phenyl)anthracene-2,6-diyl)dipyridine ( AnFPy ) were designed and synthesized as electron transporters. Their photophysical properties, energy levels and electron mobilities can be readily regulated through tuning the quantity of the pyridine ring. Through optimizing electron injection/transporting properties, AnTPy exhibits not only a suitable lowest unoccupied molecular orbital (LUMO) energy level for electron injection into light-emitting layer (EML), but also a relatively high electron mobility of around 10 −3 cm 2 V −1 s −1 , which is about two orders of magnitude higher than that of the widely used material Alq 3 . As expected, the blue fluorescent OLEDs with AnPy , AnTPy and AnFPy as an electron-transporting layer (ETL) exhibited superior performance compared to that using Alq 3 , remarkably lowering the driving voltages and improving efficiencies. In particular, the device with AnTPy as an ETL showed a maximum current efficiency of 14.4 cd A −1 , a maximum power efficiency of 12.1 lm W −1 , a maximum external quantum efficiency (EQE) of 8.15% and low efficiency roll-off even at an illumination-relevant luminance of 10,000 cd m −2 . These results clearly demonstrated that tuning electron injection/transporting properties by optimizing the number of peripheral electron-withdrawing groups was an efficient strategy to achieve high-performance ETMs.

A highly soluble and polymerizable derivative of 9,10-diphenylanthracene was designed and synthesized specifically to be capable of achieving very high loadings (at least 50 wt.%) when copolymerized with a polyvinyltoluene (PVT) matrix. The resulting heavily crosslinked plastics are mechanically hard and robust, and were found to have exceptional clarity with no sign of dye precipitation. Samples of these plastics both with and without added wavelength shifter were characterized for light yield, scintillation decay, and pulse shape discrimination (PSD) performance for α / γ discrimination, and the results were compared to that of a commercially available PSD plastic, EJ-299-34. The best performing formulation, with a primary dye loading of 50 wt.%, had a measured light yield of 9950 photons/MeV, and achieved a PSD figure-of-merit (FOM) of 1.05, the latter indicating that while the present material is not suited for practical applications, the overall approach demonstrates a proof-of-concept of PSD in highly loaded plastics stabilized through copolymerization of the primary dye, and suggests that further improvements through better dye choice/design may yet be achievable.

Single crystals of 9,10-diphenylanthracene (DPA) were grown by slow evaporation solution growth technique. The grown crystal was confirmed by single crystal. Powder X-ray diffraction was carried ou...

Raman microscopy in the lattice phonon region coupled with X-ray diffraction have been used to study the polymorphism in crystals and microcrystals of the organic semiconductor 9,10-diphenylanthracene (DPA) obtained by various methods. While solution grown specimens all display the well-known monoclinic structure widely reported in the literature, by varying the growth conditions two more polymorphs have been obtained, either from the melt or by sublimation. By injecting water as a nonsolvent in a DPA solution, one of the two new polymorphs was predominantly obtained in the shape of microribbons. Lattice energy calculations allow us to assess the relative thermodynamic stability of the polymorphs and verify that the energies of the different phases are very sensitive to the details of the molecular geometry adopted in the solid state. The mobility channels of DPA polymorphs are shortly investigated.

Theoretical schemes to evaluate electronic coupling elements for triplet–triplet annihilation (TTA) processes are proposed using fragment molecular orbital-linear combination of molecular orbital methods. Combining them with the Marcus formula, we estimate rate constants of TTA for 9,10-diphenylanthracene (DPA). We also performed molecular dynamics simulations of diffusion of DPAs in solution to estimate rate constants of molecular encounter in an assumed diffusion-controlled reaction. On the basis of the calculated rate constants, the mechanism of TTA process for DPAs in solution are discussed.

The fusion enthalpies and the heat capacities of crystalline, molten, and supercooled liquid rubrene (Tm = 603 K) and 9,10-diphenylanthracene (Tm = 523 K) were measured using fast scanning calorimetry and conventional DSC. The experimental fusion enthalpies at the melting temperature were corrected to 298.15 K according to Kirchhoff’s law of thermochemistry. On the other hand, the fusion enthalpies at 298.15 K were determined from the solution enthalpies of these compounds in benzene, considering “like dissolves like” principle. The fusion enthalpies at 298.15 K obtained using independent methods were in mutual agreement. The heat capacity corrections of the fusion enthalpies of the studied non-planar polycyclic aromatic hydrocarbons to 298.15 K were found to be significantly higher than for planar polyaromatics. The features of measurement of the heat capacities of organic compounds by fast scanning calorimetry in the temperature range of notable volatility were discussed. The complete absence of the mass losses during heating-cooling cycles was found to be unnecessary condition for accurate heat capacity measurement; tolerable mass losses during the procedure were evaluated.

Several metal-free, nonaqueous, disproportionation redox-flow-battery chemistries based on electrochemically active organic molecules are presented. The electrochemistry of 9,10-diphenylanthracene (DPA), a polycyclic aromatic compound, involves two reversible redox couples separated by more than 3 V, which are associated with electrochemical disproportionation of the neutral molecule. Nonaqueous solvents are investigated with the dual aims of realizing this high voltage in a battery cell and maximizing active-species solubility. Functionalized DPA analogues are synthesized and shown to exhibit electrochemical responses similar to pristine DPA; appending diethyleneglycoxy esters on each phenyl group to form DdPA (9,10-Bis(4-(2-(2-methoxyethoxy)ethoxy)carbonyl-phenyl)anthracene) improves solubility over DPA by a factor of 20 in acetonitrile and 5 in dimethoxyethane. The 0.21 M maximum concentration of DdPA in dimethoxyethane suggests an energy density of 8 Wh l−1, which begins to approach the energy density of state-of-the-art aqueous RFBs. Charge/discharge of a stagnant one-dimensional cell delivers the highest cell voltages from an organic single-active-species RFB chemistry yet reported. Energy and power efficiencies for DPA in dimethoxyethane and DdPA in acetonitrile are similar to nonaqueous vanadium acetylacetonate in cells of similar construction.

A new, efficient electrochemiluminescent (ECL) system based on a 9,10-diphenylanthracene/polyvinyl butyral film modified glassy carbon electrode and a tetraphenylborate anion coreactant is described. The system demonstrates strong dependence of its response on the potential scan rate. In pulsed excitation mode, the system allows for tetraphenylborate detection at a level down to 5 nM with a broad range of linear responses. The anodic cyclic voltammetry response of the system shows 2 distinct ECL waves. It was found that the first of them is due to the reaction of an oxidized fluorophore with tetraphenylborate while the second one is due to the oxidation of tetraphenylborate only. The presented results demonstrate the high potential of the tetraphenylborate coreactant for exciting pulsed ECL in fluorescent species/labels immobilized on the electrode surface, which has application potential for a number of existing ECL assay systems. Due to the ability of tetraphenylborate ions to interact with a number of cations and inorganic oxidants, the developed ECL system can also be applied for quantification based on ECL quenching that was demonstrated on the examples of hydrogen peroxide and hypochlorite.

This work assesses the reliability of different van der Waals (vdW) methods to describe lattice vibrations of molecular crystals in the framework of density functional theory (DFT). To accomplish this task, calculated and experimental lattice phonon Raman spectra of a pool of organic molecular crystals are compared. We show that the many-body dispersion (MBD@rsSCS) van der Waals method of Ambrosetti et al. and the pairwise method of Grimme et al. (D3-BJ) outperform the other tested approaches (i.e., the D2 method of Grimme, the TS method of Tkatchenko and Scheffler, and the nonlocal functional vdW-DF-optPBE of Klimeš et al.). For the worse-performing approaches the results could not even be fixed by the introduction of scaling parameters, as commonly used for high-energy intramolecular vibrations. Interestingly, when using the experimentally determined unit cell parameters, DFT calculations using the PBE functional without corrections for long-range vdW interactions provide spectra of similar accuracy as the MBD@rsSCS and D3-BJ simulations.

Two new contorted polycyclic aromatic hydrocarbons (PAHs) 1 and 2 were synthesized by acid-catalyzed benzannulation of a substituted anthracene. The isomers reveal dissimilar photophysical and redox properties with 2 having a much smaller HOMO-LUMO gap than 1. In the solid state, 2 packs in a unique two-dimensional herringbone motif that gives rise to efficient ambipolar charge transport in OFET devices, a feature not previously observed in contorted PAHs. On the other hand, 1 packs in one-dimensional dimerized π-stacks and displays insulating properties.