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Visible and infrared spectroelectrochemistry of Fe(OEPone)(NO) (H₂OEPone = octaethylporphinone) were examined in methylene chloride and THF. The visible spectra of Fe(OEPone)(NO) were similar in both solvents. Unlike other ferrous porphyrin nitrosyls, a six-coordinate complex was formed with THF as a ligand. This led to two nitrosyl bands in the infrared spectrum. The absorbance of these bands depended on the concentration of THF in the solution. Solvation and coordination effects on the carbonyl and nitrosyl bands were observed for both the nitrosyl and reduced-nitrosyl complexes. DFT calculations were carried out to interpret the spectral changes.

Marquette University, Raynor Memorial Libraries, Chemistry Research Data: https://epublications.marquette.edu/chem_data/1/

Herein, we report a novel layered lead bromide, (CH₃CH${}_2{)}_3$N${}^{+}$Br${}^{-}$(CH${}_2{)}_2$NH${}_3^{+})$PbBr₃, where bulky organic cations, (CH₃CH${}_2{)}_3$N${}^{+}$Br${}^{-}$(CH${}_2{)}_2$NH${}_3^{+})$, amino-ethyl triethyl ammonium [aetriea] were not only incorporated between the inorganic layers but also sandwiched within the inorganic [PbBr₆]${}^{4-}$ octahedral layered structure. The UV-Visible, photoluminescence spectroscopy (PL), X-ray diffraction (XRD) and a field-emission scanning electron microscope (FE-SEM) result show that the new perovskitoid has a microrod shape with an estimated bandgap of $\sim$3.05 eV. The structural and optoelectronic properties of the [aetriea]PbBr₃perovskitoid were further corroborated by first-principles density functional theory (DFT) calculations. Thermogravimetric analysis (TGA) data show good stability of the [aetriea]PbBr₃perovskitoid. Time-resolved photoluminescence (TRPL) decays from new [aetriea]PbBr₃perovskitoid showing 6 ns average lifetime. These results suggest that doubly charged cation hybrid perovskite materials are potential candidates for optoelectronic applications.

Flexible dielectric polymers that can withstand high electric field and simultaneously have high dielectric constant are desired for high-density energy storage. Here, we systematically investigated the impact of oxygen-containing ether and carbonyl groups in the backbone structure on dielectric properties of a series of cyclic olefin. In comparison to the influence of the –CF₃ pendant groups that had more impact on the dielectric constant rather than the band gap, the change of the backbone structure affected both the dielectric constant and band gaps. The one polymer with ether and carbonyl groups in the backbone has the largest band gap and highest discharge efficiency, while it has the lowest dielectric constant. The polymer without any ether groups in the backbone has the smallest band gap and lowest discharge efficiency, but it has the highest dielectric constant. Polymers that have no dipolar relaxation exhibit an inversely correlated dielectric constant and band gap. Enhancing the dipolar relaxation through rational molecular structure design can be a novel way to break through the exclusive constraint of dielectric constant and band gap for high-density energy storage.

This study analyzes the impact of zinc oxide (ZnO) decoration on the structure, stability and electronic properties of the alkyl-substituted thiophene-vinyl carbazole (3-MeTH-VCZ) copolymer, employing density functional theory (DFT)-based quantum atomistix toolkit (ATK) software. This analysis shows a negative interaction energy between the ZnO and the pristine 3-MeTH-VCZ, facilitating substantial charge transfer. Furthermore, the composite (3-MeTH-VCZ-ZnO) formed by the decoration of ZnO in the pristine 3-MeTH-VCZ shows improved electronic properties compared to its pristine counterpart. This improvement is evidenced by an approximate 62% reduction in the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap, confirmed by shifts observed in the molecular energy spectrum (MES) and density of state (DOS) profiles. The reduction in the HOMO-LUMO gap suggests enhanced physicochemical and electrochemical sensitivity of the synthesized composites to external stimuli, making them promising candidates for sensing and optoelectronic devices.