Aromatic Bridges Research Articles

Tailoring Optoelectronic Properties of A-D-A Type Non-Fullerene Acceptors with Fused Aromatic Thiophene-Furan Bridges for Efficient Organic Photovoltaics

Tailoring Optoelectronic Properties of A-D-A Type Non-Fullerene Acceptors with Fused Aromatic Thiophene-Furan Bridges for Efficient Organic Photovoltaics

Enhanced Hyperpolarizabilities Through p‐Phenylene Bridges: Computational Studies on Metamerism and Functional Molecular Properties of Pyridinium–Dicyanomethanide‐Based Zwitterions

ABSTRACTPara‐phenylene‐bridged pyridinium (acceptor)–dicyanomethanide (donor)‐based zwitterions were computationally investigated and are reported here. Reichardt's metamer was found to be twisted and Brooker's metamer in near‐planar conformation. Natural bond orbital (NBO) analysis showed that mesomeric resonance is helping Brooker's metamer but found to be not helpful for Reichardt's metamer. To assess the impacts of metamerism and aromatic bridges, fundamental molecular properties like dipole moments (μ), polarizabilities (α), hyperpolarizabilities (β), and adiabatic absorptions of these two molecules were analyzed and then directly compared with their counterpart zwitterions without any bridges (previously reported). Results of impact of metamerism: Reichardt's metamer showed around three times enhanced hyperpolarizabilities (ωB97xD: β = 1577.1 × 10−30 esu) than the Brooker's metamer (ωB97xD: β = 532.5 × 10−30 esu). Impacts of p‐phenylene bridges: Compared to their respective D–A directly connected zwitterions reported previously (in ωB97xD methodology, Reichardt's: β = 257.2 × 10−30 esu and Brooker's: β = 67.2 × 10−30 esu), respective p‐phenylene‐bridged zwitterions showed five to eight times enhanced hyperpolarizabilities. This report highlights the better efficiencies of Reichardt's metamer over Brooker's metamer and aromatically bridged over the directly connected zwitterions. Current findings may be helpful in the designing of efficient functional molecular chromophores, and aromatic bridge combined with zwitterions can be solutions to nonlinear transparency trade‐off problem.

Enhanced molecular first hyperpolarizabilities with Reichardt’s type of zwitterions: a computational study on roles of various monocyclic aromatic bridges

ContextThis work reports structure–property correlations of 27 zwitterions Reichardt’s types of zwitterions. Focuses are twofold, to see the (1) impacts of metamerism with Reichardt’s vs Brooker’s types of zwitterions and (2) impacts of monocyclic aromatic rings as bridges. All the molecules considered here have pyridinium (common acceptor: A) and p-phenylene-dicyanomethanide (common donor: D). Fundamental molecular properties like dipole moments (μ), polarizabilities (α), hyperpolarizabilities (β), and adiabatic absorptions were computed only for the Reichardt types and compared with the literature reported respective Brooker’s types of zwitterions. As an impact of metamerism, in general 2–3 times enhanced hyperpolarizabilities (β) were observed for Reichardt’s compared to Brooker’s types. Exceptions were observed with some triazine bridges and furan bridge, where Brooker’s types were found to be more efficient. As impacts of aromatic bridges, in general, 6–sevenfold enhanced β compared to well-known traditional bridges and enhanced β were observed compared to D-A directly connected zwitterion (benzene bridge: sixfold enhanced β). Current findings show that the aromatic bridge control with Reichardt’s types of zwitterions is more efficient and thus may be employed as an effective strategy for the designing of functional molecular chromophores for various other fundamental areas.MethodsAll computations were performed with Gaussian 09. Geometry optimizations and computations of fundamental properties were carried out with HF, B3LYP, CAM-B3LYP, and ωB97xD methodologies, with 6-31G(d,p) and aug-cc-pVDZ basis sets. For adiabatic excitations, computations were carried out using TDDFT and TDHF approaches. For the computations of the response properties (like the nonlinear optical responses), CPHF approach was used.

Design, Synthesis, and Theoretical Studies on the Benzoxadiazole and Thienopyrrole Containing Conjugated Random Copolymers for Organic Solar Cell Applications.

In this study, six different donor-π-acceptor1-π-donor-acceptor2 type random co-polymers containing benzodithiophene as a donor, benzooxadiazole (BO), and thieno[3,4-c]pyrrole-4,6-dione (TPD) as acceptor, have been synthesized and characterized. In addition to the acceptor core ratio at different values, the effect of aromatic bridge structures on the optical, electronic, and photovoltaic properties of six different random co-polymers is investigated by using thiophene and selenophene structures as aromatic bridge units. To investigate how the acceptor unit ratio and replacement of aromatic bridge units impact the structural, electronic, and optical properties of the polymers, density functional theory (DFT) calculations are carried out for the tetramer models. The open-circuit voltage (VOC), which is strongly correlated with the HOMO levels of the donor material, is enhanced with the increasing ratio of the TPD moiety. On the other hand, the short-circuit current (JSC), which is associated with the absorption ability of the donor material, is improved by the increasing ratio of BO moiety with the π-bridges. BO moiety dominant selenophene π-bridged co-polymer (P4) showed the best performance with a power conversion efficiency (PCE) of 6.26%, a JSC of 11.44mAcm2, a VOC of 0.80V, and a fill factor (FF) of 68.81%.

Click estradiol dimers with novel aromatic bridging units: synthesis and anticancer evaluation

Estradiol dimers (EDs) possess significant anticancer activity by targeting tubulin dynamics. In this study, we synthesised 12 EDs variants via copper-catalysed azide-alkyne cycloaddition (CuAAC) reaction, focusing on structural modifications within the aromatic bridge connecting two estradiol moieties. In vitro testing of these EDs revealed a marked improvement in selectivity towards cancerous cells, particularly for ED1–8. The most active compounds, ED3 (IC50 = 0.38 μM in CCRF-CEM) and ED5 (IC50 = 0.71 μM in CCRF-CEM) demonstrated cytotoxic effects superior to 2-methoxyestradiol (IC50 = 1.61 μM in CCRF-CEM) and exhibited anti-angiogenic properties in an endothelial cell tube-formation model. Cell-based experiments and in vitro assays revealed that EDs interfere with mitotic spindle assembly. Additionally, we proposed an in silico model illustrating the probable binding modes of ED3 and ED5, suggesting that dimers with a simple linker and a single substituent on the aromatic central ring possess enhanced characteristics compared to more complex dimers.

Molecular simulation of the regulation mechanism of surfactant on microscopic chemical wetting of coal

To explore the influence mechanism of surfactants on the wettability of coal, elemental analysis, Fourier-transform infrared spectroscopy, 13C nuclear magnetic resonance spectroscopy, and X-ray photoelectron spectroscopy were applied to characterize the chemical structure of coal before and after modification with solutions having different concentrations of sodium dodecyl sulfate. Macromolecular models of four different coal samples before and after modification were constructed, and the mechanism of the change in the chemical structure of the coal before and after modification on its wettability was then studied with molecular dynamics (MD) simulations. The molecular formulas of the four coal samples were determined to be C160H114O34N2S, C203H144O44N3S, C196H137O42N3S, and C242H171O56N3S. Aromatic carbon accounts for a relatively high proportion of these formulas, mainly in the form of benzene rings and naphthalene. The ratios of aromatic bridge carbons to pericarbons are 0.3, 0.23, 0.21, and 0.22, respectively. Nitrogen (N) and sulfur (S) are present as pyrrole nitrogen and thiol thiophenol, respectively. MD simulations show that compared with the original coal sample, the thickness of the absorption layer between the modified coal and water molecules increases, and the interaction energy is enhanced. The maximum electrostatic potential of the surface of coal molecules in the four systems (−0.07826, −0.07915, −0.08511, and −0.10711 a.u.) is concentrated around the oxygenated functional groups. After the modification, the distribution of oxygenated functional groups is more extensive, and the content of water molecules adsorbed on the surface of the coal increases because of static electricity, which promotes the wettability of the coal. This research reveals the microscopic wetting mechanism of coal dust at the molecular level and provides a research path that offers important guidance for the reduction of coal dust that is generated during mining.

Abstract 7142: Optimizing estradiol dimers through linker design: Enhancing anticancer efficacy by targeting microtubule dynamics

Abstract We investigated the development and anticancer efficacy of novel estradiol dimers (ED), targeting the dynamics of microtubules—an essential factor in effective cancer therapy. Employing copper-catalyzed azide-alkyne cycloaddition (CuAAC), two distinct series of ED variants were synthesized. The initial series included thirteen dimers, derived from 17α-ethinyl estradiol, incorporating varied five-atom linkers with central carbon, nitrogen, or oxygen atoms, and, in some instances, modified with benzyl groups containing hydroxy or methoxy substituents. These dimers were evaluated for their cytotoxic properties and impact on the cell cycle, revealing certain structures with substantial efficacy, compared with the original ED. The subsequent series, encompassing twelve variants, concentrated on structural alterations within the aromatic bridges linking the estradiol units. In this series, linkers of simpler composition and fewer substituents demonstrated increased selectivity and potency against cancer cell lines, particularly ED3 and ED5, which exhibited cytotoxicity levels comparable to established tubulin inhibitors. Both dimers series showed the ability to disrupt microtubule assembly and mitotic processes, confirmed through cell-based evaluations and in vitro tubulin assembly assays. Complementing these results, in silico modelling and binding free energy calculations exhibited a strong correlation with the demonstrated biological activities, especially in terms of binding affinity to the colchicine site. Collectively, these findings highlight the promise of estradiol dimers as potential anticancer agents and emphasize the critical role of linker structures in enhancing their biological effectiveness. Work was supported by the Ministry of Education, Youth and Sports of the Czech Republic through infrastructural projects (CZ-OPENSCREEN - LM2018130; EATRIS-CZ - LM2018133) and National Institute for Cancer Research (Programme EXCELES, ID Project No. LX22NPO5102) - Funded by the European Union - Next Generation EU. Citation Format: Petr Dzubak, Michal Jurášek, Jiří Řehulka, Soňa Gurská, Pavel Polishchuk, Pavel Dráber, Lukáš Huml, Pavel B. Drašar, Alexandra Ivanova, Olena Mokshyna, Lenka Hrubá, Marián Hajdúch. Optimizing estradiol dimers through linker design: Enhancing anticancer efficacy by targeting microtubule dynamics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7142.

Comprehensive quantum chemical study of the associative complex of para-aminobenzoic acid and 7-diethylamino 4-methyl coumarin by adsorption and aromatic bridges.

The present study accounts for the quantum chemical and nonlinear optical properties of the combination of para-aminobenzoic acid and 7-diethylamino 4-methyl coumarin. Three different complexes were designed, surface interaction (adsorption) and two by connecting both molecules with π-bridge benzene and biphenyl. The amino and carboxyl groups were observed to behave as strong donor and acceptor sites in all the complexes. The band gap of the adsorbed complex was found more suitable. The absorption wavelength and intensity both were seen to increase with the increase in the number of benzene rings in the π-bridge. The values of first- and second-order hyperpolarizability suggest the improved nonlinear optical responses of the introduced complexes. Additionally, the negative value of second-order hyperpolarizability suggests the possibility of the occurrence of reverse saturable absorption in these combinations. The reported work gives theoretical insights into the nonlinear optical properties of the combination of para-aminobenzoic acid and 7-diethylamino 4-methyl coumarin. The molecular modeling and the quantum chemical studies were performed with Gaussian software packages. The standard B3LYP-6-311++G(d,p) basis functionals were used for energy minimization and other spectral calculations. All the surface analyses reported here are obtained by employing Multiwfn software. The chemical reactivity was established by the global reactivity descriptors. The intramolecular interactions and charge localization were stated using inter-fragment charge transfer analysis.

Enhanced optoelectronic properties with aromatic bridges: A computational study on N‐methyl pyridinium and phenolate types of push‐pull zwitterions

AbstractA series of zwitterions with varying bridges, connecting N‐methyl pyridinium acceptor, with phenolate donor, are investigated using various methodologies like, HF, B3LYP, CAM‐B3LYP and ωB97xD. In this systematic study effects of various mono aromatic rings as bridges, on the response properties like, the dipole moments (μ), polarizabilities (α), hyperpolarizabilities (β) and adiabatic absorptions were analyzed using CPHF and TDDFT (or TDHF) theories. Compared to many traditional bridges, as well as without a bridge, enhanced nonlinear optical (2ND order NLO) responses were observed for these aromatically bridged zwitterions (with benzene ring as bridge ~5.3 times and ~7.9 times enhanced hyperpolarizabilities were observed compared to either the ethylene bridge or without any bridge cases, respectively). Also, many significant differences and large enhancements in response properties were observed compared to our earlier works on non‐zwitterionic system (~4.3 times enhanced hyperpolarizability—benzene as bridge case). For some bridge cases, 10‐ to 15‐fold enhanced hyperpolarizabilities were observed compared to without any bridge case. This work reports a class of non‐TICT chromophores, promoting bridge aromaticity control on structure–property correlation, as a suitable and efficient chromophore design strategy to create a wide range of function molecular chromophores. Also, unidirectional natures of response properties and large dipole moments can make these zwitterions suitable 1D‐molecular materials for various contemporary technological applications, as poled polymer‐based materials.

Synthesis, characterization, DNA/BSA-binding affinity and biological activity of dinuclear palladium(II) complexes with aromatic N-heterocyclic bridging ligand

Dinuclear palladium(II) complexes, [{Pd(en)Cl}2(μ-L)](NO3)2 (L is bridging ligand pirazine (Pd1), pyrimidine (Pd2), pyridazine (Pd3), phenazine (Pd4) and en is ethylenediamine), were synthesized and characterized. The interactions of the synthesized palladium(II) complexes with biomolecules such as DNA and BSA were studied using UV–Vis spectroscopy and fluorescence spectroscopy. Analysis of tumoricidal activity of investigated complexes, tested on several tumor cell lines of human and mouse origin, revealed that Pd1 and Pd2 exhibited weak cytotoxic potential at lower concentrations. However, Pd3 showed higher cytotoxicity effects on the human MDA-MB 468 breast carcinoma and A375 melanoma cell lines, while Pd4 exhibited tumoricidal potential against MDA-MB 468 cells and A549 human lung adenocarcinoma cells. Interestingly, A375 human melanoma cells were highly sensitive to Pd4 treatment similarly to the effect of cisplatin. Further, the antimicrobial effects of tested compounds were evaluated using different species of Gram-positive and Gram-negative bacteria, as well as yeasts. Pd1–Pd4 showed variable antimicrobial activity depending on the microorganism species. Among tested complexes, Pd4 exhibited the highest antimicrobial activity. The obtained data suggest that palladium(II) complexes might be further investigated as potential antitumor and antimicrobial agents.

Study on the interaction and coking characteristics of low-sulfur meager coal and medium-high sulfur fat coal during co-carbonization process

To expand the scope of coking coal resources and realize the efficient utilization of different types of coking coals, medium-high sulfur fat coal (FC1, FC2) and low-sulfur meager coal (MC) were selected to explore the influence of co-carbonization process on the final coke properties. Using 13C NMR, Raman and FTIR characterization, it is found that FC1 has a higher content of methylene and aromatic bridge carbon, multiple aromatic structure of 3–5 benzene ring, strong branching degree and hydrocarbon generation ability than FC2, which promote FC1 to produce more liquid phase products in the thermoplastic stage, form higher mobility and better fuse with MC. Comparing the properties of coke with different ratios, it is found that the proportion of MC added in FC1 could reach 60%, the cold-state strength of coke was improved and the deterioration of thermal-state strength was unobvious. When the amount of MC in FC2 is 40%, better coke performance can be obtained. This is mainly due to the fact that the actual volatile released during the pyrolysis of FC1 and FC2 combined with MC is higher than the calculated value, this promoted the pyrolysis of Car-Cal/O and inhibited the pyrolysis of Cal-Cal and Car-Car, resulting in more intermediate molecular weight aromatic nuclei and higher 3–5 membered ring structure content in the thermoplastic process, thus improving the coke quality.

Construction of macromolecular structure in KunNing coal and analysis of Macro-Micro oxidation characteristics

To explore the macro–micro coal oxidation characteristics for the purpose of preventing coal spontaneous combustion and achieving efficient coal conversion and utilization, the enclosed coal oxidation characteristics of KunNing coal sample (KN) under 25–70 °C were investigated. KN coal molecular models were constructed based on analysis and testing results of X-ray Photoelectron Spectroscopy (XPS), Carbon-13 Nuclear Magnetic Resonance Spectroscopy (13C NMR), Fourier Transform Infrared Spectroscopy (FTIR) and other techniques. The pyrolysis processes of coal-oxygen reaction systems with different oxygen contents were simulated using ReaxFF force field. The results show that the oxygen consumption rate, CO release rate, CO2 release rate and oxidation heat release intensity of coal increase exponentially with rising temperature. The ratio of aromatic bridge carbon to peripheral carbon in KN coal molecular structure is 0.08, and the molecular formula is C149H76O15N2S2. In the later stage of the experimental and molecular dynamics simulation processes, the CO content decreased while the growth rate of CO2 increased. Different indicator gases exhibit varied responses to oxygen content. The C-atom labeling and traceback results for the four indicator gas molecules demonstrate that CO2 mainly comes from aldehyde, hydroxyl, carboxyl and methoxy groups in coal molecules, CO is primarily generated from esters, phenols, carbonyls, C2H2 is predominantly derived from ring-opening and cracking of cycloalkanes, and the source of C2H4 is related to cycloalkanes and alcohols.

Roles of bridges on Electronic, linear and nonlinear optical Properties: A computational study on zwitterions with N-methyl pyridinium and p-Dicyanomethanide phenylene

This contribution reports structure–property correlations for a series of interesting zwitterions. All the molecules have N-methyl pyridinium as common acceptor (A), dicyanomethanide substituted p-phenylene as common donor (D), coupled through several mono aromatic rings as the bridges. Computations were carried out using HF, B3LYP, CAM-B3LYP and ωB97xD methodologies. The current report deals with a complete methodical study on the effects of various possible mono aromatic rings as bridges, on dipole moments (μ), polarizabilities (α), hyperpolarizabilities (β) and adiabatic absorption properties. This work shows that compared to literature reported traditional bridges, aromatic bridges indeed showed enhanced nonlinear optical responses (10-fold enhanced β in some cases). Results show that unlike the TICT approach, one can be able to design a wide range of non-TICT chromophores by suitable manipulations through aromatic bridges. Aromatic control on the bridges is suggested as an effective approach in the designing of a wide range of efficient molecular chromophores.

Model construction and optimization of coal molecular structure

Understanding the structural characteristics of coal molecular at the molecular level is of paramount importance for the effective utilization of coal. In this work, the molecular structure of coal sample, from Liuzhuang(LZ) Coal Mine in Anhui Province, China, is investigated using modern analytical techniques, such as elemental analysis, X-ray photoelectron spectroscopy (XPS),Fourier Transform Infrared Spectroscopy(FT-IR) and Solid 13C nuclear magnetic resonance spectroscopy (13C NMR). It is found that the aromatic compounds of LZ coal are mainly in the form of 2 and 3 rings, with an aromaticity of 40.99% and the ratio of aromatic bridge carbon to aromatic peripheral carbon is 0.232. sulfur element is too low to considered in the model. Based on the above analysis, the molecular formula of LZ coal is inferred as C158H143O35N7. The experimental 13C NMR is consistent with the simulated spectrum, which indicates the accuracy of LZ molecular structure model. The molecular structure model is constructed and optimized by using classical molecular dynamics and the density functional based tight-binding method to obtain the lowest energy and most stable conformation, respectively. The optimized model has a more prominent steric configuration, but the lamellar structure of the aromatic layer is arranged in a more disordered manner. The experimental FT-IR spectra of the model are in preferably good agreement with the simulated results, which proves the correctness of LZ molecular structure. The molecular structure of LZ mine coal established in this paper can provide basic scientific data for further investigation of gas adsorption and resolution in coal seams at the atomic and molecular scales. Overall, Compared to contemporary technologies, these results show a good comparability among the different techniques and therefore provide comprehensive, accurate analytical technique to analyze the molecular structure of coal.

Experimental and theoretical study on molecular structure construction of Hongliulin coal

A suitable model can reflect the properties of coal well. In this study, the properties of HongLiuLin (HLL) coal were studied through industrial analysis, XPS, 13C NMR and FTIR. The results show the coal has middle-rank bituminous coal characteristics, and the ratio of aromatic bridge carbon to aromatic peripheral carbon is 0.16. Benzene and naphthalene ring are the main components of the aromatic structure. N and S exist in pyrrole nitrogen and fatty sulfur, respectively. The hypothesis method was used to deduce the molecular formula C130H73O21NS of the coal model. The stability of the carbon skeleton was improved through the Van Der Waals (VDW) forces in non-bonding energy. Verification of NMR, FTIR and density was completed based on quantum chemistry and molecular mechanics. The coal model energy level orbitals analysis shows that the LUMO and HOMO orbitals are located in the aromatic functional groups. This work provides a reference for further research on the nature of coal in north Shaanxi and improving the utilization rate of coal.

Vanillin-Based Epoxy Vitrimers: Looking at the Cystamine Hardener from a Different Perspective.

Epoxy vitrimers encompass many advantages compared to traditional epoxy materials such as recyclability, repairability, and reprocessability. These properties are induced by the incorporation of dynamic reversible covalent bonds. Recently, the incorporation of aromatic disulfide bridges that are dynamic has expanded the development of new eco-friendly epoxy materials. Herein, we studied a bio-based aliphatic disulfide based on cystamine as a hardener with a vanillin-derived bio-sourced epoxy to prepare fully bio-based epoxy vitrimers. This article provides a comparative study between cystamine and an aromatic disulfide benchmark hardener issued from petrol resources. This work demonstrated that the presence of this aliphatic hardener has a significant influence not only on the reactivity, but most importantly on the resulting dynamic properties. An interesting yet counterintuitive accelerating effect of the dynamic exchanges was clearly demonstrated with only 2 to 20% of molar fraction of cystamine added to the aromatic disulfide formulation. A similar glass transition was obtained compared to the purely aromatic analogue, but relaxation times were decreased by an order of magnitude.

Construction of macromolecular model and analysis of oxygen absorption characteristics of Hongyang No. 2 coal mine

Understanding the molecular structure characteristics of coal from the molecular level is of great significance for realizing rational utilization and efficient transformation of coal. The molecular structure of coal samples from 1304 working face in No.13 coal seam of Hongyang No.2 Mine (HY) was studied by industrial analysis, elemental analysis, Nuclear magnetic resonance carbon spectroscopy (13C NMR) and Fourier transform infrared spectroscopy (FTIR). The results show that the aromatic compounds in coal samples of HY are mainly naphthalene ring structures. The aliphatic structure mainly consists of methyl, ethyl side chains and cycloalkanes. The ratio of aromatic bridge carbon to weekly carbon in molecular structure is 0.17. Oxygen atoms exist in the form of carbonyl, hydroxyl, and ether bonds, nitrogen atoms exist in the form of pyridine and pyrrole respectively, and sulfur atoms exist in the form of thiophene. Based on this, the planar structure model of coal macromolecule in HY is constructed, and its molecular formula is C129H88O29N2S, and its molecular weight is 2160. The structure optimization and annealing kinetics simulation of a single macromolecule model were carried out, and a stable three-dimensional coal model of HY was obtained. In addition, the oxygen absorption characteristics of coal samples in HY were studied by molecular dynamics and quantum chemistry. The results show that the adsorption capacity of the Wiser model is less than that of HY coal model. This is because, compared with the Wiser model, the content of oxygenated aliphatic hydrocarbons in the molecular structure of HY coal is higher, and the condensation degree of polycyclic aromatic hydrocarbons is lower. Due to the stronger physical adsorption capacity of hydroxyl, ether bond, and carbonyl on O2, HY Mine has stronger physical adsorption capacity on O2.

Understanding the molecular structure of Datong coal by combining experimental and computational study

Understanding the structure of coal is crucial to explain its chemical reactivity. In order to study the microstructure characteristics of coal in-depth, ultimate analysis, solid-state 13C nuclear magnetic resonance (13C-NMR), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) are used to analyze the Datong coal. The results show that the aromaticity of Datong coal is 62.60%, and the ratio of aromatic bridge carbon to aromatic peripheral carbon is 0.238, indicating that more naphthalene and anthracene are in the aromatic structure of coal. Hydroxyl (C–O), carbonyl (C=O) and carboxyl (COO–) are the main oxygen-containing groups in coal, and the nitrogen element mainly exists in the form of pyrrole and pyridine. The main substitution modes on the benzene ring are di- and tri-substituted. Based on the above analysis, the 2D and 3D macromolecular models are constructed and optimized by using computer-aided modeling. The model is verified by 13C-NMR and FTIR spectra with density functional theory calculations. The coal molecular formula is defined as C149H112O24N2. The reaction sites in coal structure are oxygen-containing functional groups and aliphatic structures (–CH, –CH2). Therefore, the molecular structure of Datong coal has been systematically described and understood at the molecular level based on experimental data and quantum chemical calculations.

Isoquinoline-1,3-dione-derived conjugated polymers for field-effect transistors: synthesis, properties, and the effect of inner aromatic bridges

A series of novel isoquinoline-1,3-dione (IQD)-derived conjugated polymers were designed and synthesized. They showed promising high hole mobilities up to 1.08 cm2 V−1 s−1, which are among the highest in the IQD-based polymers reported so far.

Synthesis of Conjugated bis-Schiff Base and Their Complexes as Dye-Sensitizer for Dye Sensitized Solar Cell (DSSC) Application

Schiff base and their metal complexes have been widely used as photovoltaic materials due to their excellent π-electron transfer properties along the molecule. A total of eleven conjugated symmetrical bis-Schiff base and their complexes with different π-spacers have been synthesized and spectroscopically characterized in order to investigate their conversion efficiency in dye-sensitizer solar cells (DSSC). All compounds were either substituted with hydroxy (-OH) or methoxy (-OMe) as the electron donor and difluoro boron (BF2) as the electron acceptor or without any substituent. All compounds were applied as dye-sensitizer in DSSC using titanium (IV) oxide (TiO2) coated on a fluoride doped tin oxide glass as the working electrode and electric paint containing carbon black, whereas graphene coated indium tin oxide glass as the counter electrode. The power conversion efficiencies of the eleven bis-Schiff bases were compared to N3 Dye as the benchmark standard. The results showed that the compound with aromatic ring bridge as the π-spacer and -OMe substituent gave the highest efficiency at 0.0691% whereas the compound with aromatic ring and BF2 gave the lowest efficiency at 0.0012%.