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Self-organization has been regarded as a tool for the synthesis of well-defined organic nanostructures. Heterocyclic annulated perylene diimides are the subjects of considerable current research studies. The purpose of this study is to reveal the photophysical property, electronic structure and solid-state packing of O-heterocyclic annulated perylene diimide.

Asymmetrically five-membered O-heterocyclic annulated perylene diimide (OAPDI) was synthesized. Structure and purity of OAPDI were confirmed by ¹H NMR, ¹³C NMR, IR and mass spectral techniques. Photophysical properties of OAPDI were studied using UV–vis absorption and fluorescence in both solution (CHCl₃) and solid state. Scanning electron microscopic and atomic force microscopy were used to characterize the surface morphology of OAPDI. Conducting properties of the OAPDI were evaluated by current–voltage measurements. The compounds geometries were also optimized at 6-31G* using density functional theory.

The UV–vis absorption and fluorescence spectra of OAPDI in solution are blue-shifted in comparison with that of unsubstituted perylene bisimide. Solid-state UV–vis measurements of OAPDI indicate that it is capable of forming highly ordered structure. The non-covalent interactions, electrostatic attraction and p-p stacking moieties of OAPDI synergistically guide assembly and domain growth while maintaining the interpenetrating network of nanofibers in the solid film. The OAPDI gave higher current at −2.0 V (0.68 µA) and 4.0 V (1.0 µA).

This study will be helpful for exploring feasible routes to acquire soluble perylene diimides and well-defined organic nanostructures. Furthermore, such molecular tailoring approach would be helpful for designing and synthesizing novel organic semiconductive materials with excellent charge-transporting and light-emitting capabilities.

Photoresist imaging traditionally uses silver halide or diazo based phototools for contact exposure to an actinic UV light source. By contrast, laser direct imaging uses digital imaging data to control a laser beam scanner to write directly on to the photoresist, therefore eliminating the need for phototools. In the past, even though the benefit of a UV system was recognised, laser direct imaging was mainly limited to the use of a visible laser as early UV lasers were low in power, unreliable and expensive. So far, no visible systems have gained commercial recognition because of the inherent deficiencies of the visible system. Recent advantages in UV laser equipment and UV sensitive photoresist have now made UV laser direct imaging a viable alternative to traditional contact imaging. As new UV laser imaging systems start to emerge, interest and attention are also growing among printed circuit board manufacturers. This paper discusses various attributes of a UV laser direct imaging system and fundamental differences in photophysics between laser direct imaging and conventional UV imaging.

In this study, two novel fluorescent dyes, based on naphthalimide derivatives have been synthesised from acenaphthene as a starting material. The ability of the dyes to graft to polymer chain was then demonstrated. The novel synthesised dyes and self-coloured polymers were characterised by a variety of techniques.

The novel dyes were prepared through by halogenation, oxidation, imidation and amination reactions. All steps of these processes were monitored by thin layer chromatography. The fluorescent dyes and their intermediates were characterised by differential scanning calorimeter, fourier transform infrared spectroscopy (FTIR), Proton Nuclear Magnetic Resonance (1H-NMR) and carbon-13 nuclear magnetic resonance (13-CNMR) spectroscopic techniques. The molar extinction coefficients and absorption maximum wavelength were obtained by examining the dyes and polymer solutions in Dimethylformamide (DMF) and toluene solvents. The fluorescency of novel dyes and self-coloured polymers was evaluated. Their quantum yields and Stokes shift values were determined as DMF and toluene solutions. The percentage of the covalently bounded dyes into the polymer chain was calculated.

The characterisation of the synthesised dyes and self-coloured polymers verified their structural correctness. The results of reaction dyes with resin demonstrated that the dyes were covalently bonded to the chain of an acrylic polymer (resin) containing carboxylic acid groups giving self-coloured polymers. The extent of fluorescence of the synthesised dyes and their polymers showed that compounds containing functional amino group in C-4 position of naphthalimide ring have high fluorescence properties.

This study is original. Self-coloured polymers based on acrylic were synthesised by novel naphthalimide dyes with acrylic resin for the first time, successfully. The novel dyes and their self-coloured polymers exhibit good and acceptable fluorescent activity.

In this work, A new 4–(2-aminoethylene) amino-N-(2-hydroxyethyl)-1,8-naphthalimide with intense green fluorescent was synthesized. This low molecular weight compound was immobilized by forming a covalent-bond with an acrylonitrile polymer containing carboxylic acid groups. The new prepared dye and self-coloured polymer were characterized by analytical techniques.

The synthesized compounds were characterized by TLC, DSC, FTIR, 1HNMR, 13CNMR, GPC, UV–visible and Fluorometery. The photophysical characteristics of the dye and polymer containing naphthalimide moiety in the side chain, were measured both in the absence and in the presence of Ag⁺, Cd⁺², Co⁺², Cr⁺³, Cu⁺², Fe⁺³, Hg⁺², Ni⁺², Pb⁺² and Zn⁺² cations.

The results showed that the characterization of the synthesized dye and its polymer verified their structural correctness. It is shown that dye and polymer are photo-induced electron transfer (PET) fluorescent sensors which exhibit fluorescence quenching in the presence of metal ions. Among the various metal ions, both dye and polymer are more sensitive to Fe⁺³ cations.

This study is original. A 4–(2-aminoethylene) amino-N-(2-hydroxyethyl)-1,8-naphthalimide and its self-coloured polymer were synthesized for the first time, successfully.

The purpose of this paper is to focus on the development of highly efficient emission materials for light‐emitting diodes (LEDs).

The equilibrium geometries of silole‐based derivatives are optimised by means of DFT/B3LYP method with the 6‐31G(d) basis set in this paper. The geometries of single‐excitation are optimised using the ab initio configuration interaction with single excitations/6‐31G(d), the first singlet excited states and optical properties are calculated by using time‐dependent density‐functional theory based on the 6‐31G(d) basis set.

The highest occupied molecular orbital and lowest unoccupied molecular orbital suffer larger effects from the variation of the substituent groups of methyls and phenyls. The absorption wavelengths of all the cases are similar, but the emission wavelengths are significantly different.

Solid‐state stacking effect is not included in this paper.

In view of the application of silole‐based derivatives systems, the control of photophysical properties and electronic structures by structural modification is relevant to further molecular design.

This paper aims to synthesise coumarine flourescent dyes from a cheap material in a very short time with a very high yield, and by using a clean green chemistry.

Efficient microwave synthesis for some novel iminocoumarins starts from the reaction of p-phenyl-enediamine and ethyl cyanoacetate followed by cyclocondensation with salicylaldehyde derivatives.

The synthesized iminocoumarine compounds were characterized by spectroscopic methods. Absorption and fluorescence spectra of the compounds were also recorded. All compounds were fluorescent in 1,4-dioxane solution, they all emitted blue light (440-460 nm). The printing properties were studied, and their applications on printing polyester and polyamide fabrics were studied by silk screen printing.

The authors designed efficient microwavel synthesis for some novel iminocoumarine derivatives; The novel procedure features short-reaction time, moderate yields and simple workup; All compounds were fluorescent in 1,4-dioxane solution, and they all emitted blue light; The authors studied their application in printing polyester and polyamide fabrics.

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

A series of novel symmetric and asymmetric compounds possessing third-order NLO properties were synthesized using 1,3,5-tribromobenzene as the basis. The photophysical and electrochemical properties, as well as the click reactions, were characterized by means of UV–VIS–NIR absorption spectroscopy and cyclic voltammetry.

The donor–acceptor chromophores were inserted into compound, making the molecule to have a broader absorption in the near-infrared regions and a narrower optical and electrochemical band gap. It also formed an electron-delocalized organic system, which has larger effects on achieving a third-order NLO response. The third-order NLO phenomenon of benzene ring complexes was experimentally studied at 532 nm using Z-scan technology, and some compounds showed the expected NLO properties.

The click products exhibit more NLO phenomena by performing different click combinations to the side groups, opening new perspectives on using the system in a variety of photoelectric applications.

This paper aims to prepare a new donor–π–acceptor (D–π–A) and acceptor–π– D–π–A (A–π–D–π–A) phenothiazine (PTZ) in conjugation with vinyl isophorone (PTZ-1 and PTZ-2) were designed and their molecular shape, electrical structures and characteristics have been explored using the density functional theory (DFT). The results satisfactorily explain that the higher conjugative effect resulted in a smaller high occupied molecular orbital–lowest unoccupied molecular orbital gap (Eg). Both compounds show intramolecular charge transfer (ICT) transitions in the ultraviolet (UV)–visible range, with a bathochromic shift and higher absorption oscillator strength, as determined by DFT calculations.

The produced PTZ-1 and PTZ-2 sensors were characterized using various spectroscopic methods, including Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy (¹H/¹³CNMR). UV–visible absorbance spectra of the generated D–π–A PTZ-1 and A–π–D–π–A PTZ-2 dyes were explored in different solvents of changeable polarities to illustrate positive solvatochromism correlated to intramolecular charge transfer.

The emission spectra of PTZ-1 and PTZ-2 showed strong solvent-dependent band intensity and wavelength. Stokes shifts were monitored to increase with the increase of the solvent polarity up to 4122 cm⁻¹ for the most polar solvent. Linear energy-solvation relationship was applied to inspect solvent-dependent Stokes shifting. Quantum yield (ф) of PTZ-1 and PTZ-2 was also explored. The maximum UV–visible absorbance wavelengths were detected at 417 and 419 nm, whereas the fluorescence intensity was monitored at 586 and 588 nm.

The PTZ-1 and PTZ-2 dyes leading to colorimetric and emission spectral changes together with a color shift from yellow to red.

The purpose of this study aims to synthesize a novel donor–acceptor dye based on phenothiazine as a donor (D) and nonconjugated spacer was devised and synthesized by condensing of 2,2'-(1H-indene-1,3(2H)-diylidene) dimalononitrile with aldehyde and the practical synthesis methodology as given in Scheme 1.

The prepared phenothiazine dye was systematically experimentally and theoretically examined and characterized using nuclear magnetic resonance spectroscopy (1H,13C NMR), Fourier-transform infrared spectroscopy (IR) and high-resolution mass spectrometry. Density functional theory (DFT) and time-dependent density functional theory DT-DFT calculations were implemented to determine the electronic properties of the new dye

The UV-Vis absorption and fluorescence spectroscopy of the synthesized dye was investigated in a variety of solvents with varying polarities to demonstrate positive solvatochromism correlated with intramolecular charge transfer (ICT). The probe’s quantum yields (Фf) are experimentally measured in ethanol, and the Stokes shifts are found to be in the 4846–9430 cm⁻¹ range.

The findings depicted that the novel (D-π-A) chromophores may act as a significant factor in the organic optoelectronics.

This paper aims to synthesize new benzimidazole dyes aiming to study the solvent effects on their absorption in Ultraviolet-visible spectra.

Ureido/thioureido hydrazonamide benzimidazoles (U/THB) are prepared by condensation of N-aryl-1H-benzo[d]imidazole-2-carbohydrazonoyl bromides with ureido and/ or thioureido reagents. The target products are fully characterized for structural elucidation by means of their spectral and elemental methods. Solvatochromic behavior of U/THB dyes has been studied in different polar protic solvents at room temperature.

The absorption spectra distinguish two main bands at (350 nm–442 nm) and (308 nm–382 nm) referring to n-π* and π- π* transitions of the azo groups. Dimethyl formamide induces an extremely bathochromic transition comparing to the other protic solvents. The observed bathochromic shifts indicate strong interaction with solvents in the excited state. Most dyes show one absorbance in all solvents used, so they may exist in a single tautomeric form (hydrazo form).

In the present paper, the synthesis of U/THB dyes was achieved by a simple and convenient pathway. In addition, the variations in substituents attached to the chromophoric moiety could also be studied.

The new U/THB dyes are accountable for providing good knowledge about their solvation and spectral properties of an order acceptable for industrial utilization.

Synthesis of these new benzimidazole derivatives and study of their solvation and spectral properties provides good knowledge, which is very useful in many industrial applications (e.g. dye-sensitized solar cell, etc.).

The synthesized mono azo U/THB dyes are novel members in the benzimidazole family, where no details regarding the synthesis of such dyes are reported before in the literature. They are superior in terms of preparation, multiple applications and spectral properties.