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Considering the potential advantages of minimally sized corroles for diverse applications, this study reports a facile access to cyano‐substituted derivatives via a rare CF3/CN conversion. Investigation of the fully characterized gallium, phosphorus, and cobalt complexes discloses multiple effects of the meso‐nitrile groups attached to the macrocycle. This corrole appears to be the most electron poor derivative which comes into play in the redox potentials of the corresponding complexes. Compared to its precursor, both the absorption and emission are strongly red shifted and the fluorescence lifetime and quantum yield are much larger. The coordination chemistry is affected as well, by virtue of axial ligands being perpendicular rather than parallel relative to each other. [ABSTRACT FROM AUTHOR]

This study provides an accurate description of the preparation of some new quad-compensatory phthalocyanine complexes of Zn(II) and Cu(II) substituted by 4-(4-bromo-2-formylphenoxy). Several spectroscopic techniques have been employed to characterize phthalocyanine metal complexes including FT-IR, NMR, mass spectrometry, and UV-Visible spectrophotometry. Aggregation studies have been investigated in various DMSO concentrations ranging from 2×10-6 M to 10×10-6 M. In this research, the bathochromic shift of the Q band of [Zn(Pc)] depends on the solvent type in the following ascending order: (THF< DMF< CHCl3< DMSO and H2SO4), and for [Cu(Pc)] is (THF< DMSO< DMF< CHCl3 and H2SO4) respectively. Photophysical properties of the resulting complexes have been evaluated by measuring factors such as absorption and emission. Spectral results show that both complexes 2 and 3 have the potential to be used as sensitizers in photodynamic therapy (PDT) based on their singlet oxygen efficiencies (UD = 0.41, 0.39). [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2 ) is a wide-gap semiconductor with numerous applications in photocatalysis, photovoltaics, and neuromorphic computing. The unique functional properties of this material critically depend on its ability to transport charge in the form of polarons, namely narrow electron wavepackets accompanied by local distortions of the crystal lattice. It is currently well established that the most important polymorphs of TiO2, the rutile and anatase phases, harbor small electron polarons and small hole polarons, respectively. However, whether additional polaronic species exist in TiO2, and under which conditions, remain open questions. Here, we provide definitive answers to these questions by exploring the rich landscape of polaron quasiparticles in TiO2 via recently developed ab initio techniques. In addition to the already known small polarons, we identify three species, namely a large hole polaron in rutile, a large quasi-two-dimensional electron polaron in anatase, and a large exciton polaron in anatase. These findings complete the puzzle on the polaron physics of TiO2 and pave the way for systematically probing and manipulating polarons in a broad class of complex oxides and quantum materials. [ABSTRACT FROM AUTHOR]

AbstractThe stilbene functionalized star and bent shaped π-conjugate organic donor-donor (D-π-D) molecules with decorated triphenylamine central core were synthesized via Michaelis-Arbuzov and Wittig-Horner Reaction with excellent regio-specific. The photo-physical investigations clearly indicate the synthesized molecules have excellent optical properties with UV-visible regions and hypochromic shifts. The intra-molecular charge transfer (ICT) absorption of bent and star-shaped molecules was found in the region of 369–390 and 382–390 nm. The star and bent-shaped molecules exhibited emission maximums between 444–490 and 437–476 nm. While increasing the solvent polarity, the emission maximum of TDMSPA and DMSNDMPA molecules were observed in red-shift. The excited state dipole moment changed when compared to ground state due to the triphenylamine core confirmed by the Lippert-Mataga plot. The density functional theory is good evidence; the TDMSPA molecule has a twisted configuration and supports optical and electrochemical studies. Time-correlated single photon counting (TCSPC) technique showed that the excited state fluorescence lifetime of the stilbene molecules was found to be 2.25 and 2.18 ns for star and bent shaped molecules, respectively. The synthesized molecules exhibit significantly low band-gap energies between HOMO and LUMO, and the values are observed in the range between 2.86 and 2.91 eV. The triphenylamine core-based π-conjugate organic chromophore is widely used as a bio-imaging agent in Rhizoctonia oryzae (Plant fungal pathogen) as the model and the TDMSPA was an excellent bio-imaging agent and biocompatibility with fungal and bacterial cells. [ABSTRACT FROM AUTHOR]

Photoactive supramolecular porphyrin assemblies are attractive molecules for light‐harvesting applications. This is due to their relatively non‐toxicity, biological activities and charge and energy exchange characteristics. However, the extreme cost associated with their synthesis and requirements for toxic organic solvents during purification pose a challenge to the sustainability characteristics of their applications. This work presents the first report on the sustainable synthesis, spectroscopic and photophysical characterizations of a near‐infrared (NIR) absorbing Ca(II)‐meso‐tetrakis (4‐hydroxyphenyl)porphyrin using an electrolyzed pyrrole solution. The latter was obtained by cycling the pyrrole solution across the silver nanodumbbell particle surface at room temperature. The electrolyzed solution condensed readily with acidified p‐hydroxybenzaldehyde, producing the targeted purple porphyrin. The non‐electrolyzed pyrrole solution formed a green substance with significantly different optical properties. Remarkable differences were observed in the voltammograms of the silver nanodumbbell particles and those of the conventional gold electrode during the pyrrole cycling, suggesting different routes of porphyrin formation. The rationale behind these formations and the associated mechanisms were extensively discussed. Metalation with aqueous Ca2+ ion caused a Stokes shift of 38.75 eV. The current study shows the advantage of the electrochemical method towards obtaining sustainable light‐harvesting porphyrin at room temperature without the need for high‐energy‐dependent conventional processes. [ABSTRACT FROM AUTHOR]

Purpose: 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. Design/methodology/approach: 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 Findings: 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. Originality/value: The findings depicted that the novel (D-π-A) chromophores may act as a significant factor in the organic optoelectronics. [ABSTRACT FROM AUTHOR]

The hybrid compounds (KL1–KL3) based on Keggin polyoxometalate (POM) were synthesized from the reaction between azo-imine ligands (HL1–HL3) and Keggin-type POM. Characterizations of the obtained compounds were done by elemental analyses, FTIR, MALDI-TOF, ICP-MS, UV–vis and photoluminescence spectra. To characterize the azo-imine ligands (HL1–HL3), 1H(13C)NMR methods were also used. To obtain the Cu2+ and Pt2+ complexes (POM-complexes) of the hybrid compounds (KL1–KL3), the hybrid compounds and metal salts reacted in the C2H5OH solution. The POM-complexes were characterized by the spectroscopic and analytic methods, and then their photophysical, electrochemical and antimicrobial properties were investigated. In the UV–vis spectra of the POM based hybrid compounds KL1–KL3, while ligand-centered π–π* transitions are in the range of 333–316 nm, the charge transfer transitions (CT) observed in the range of 458–453 nm. While the emission values of KL1–KL3 compounds in DMF solution are in the range of 543–552 nm, the value of hybrid complexes shifted to the range of 570–697 nm. Antimicrobial activities of hybrid metal complexes were investigated and it was determined that all complexes showed activity against penicillium spp. Thermogravimetric analysis (TGA) studies were carried out to investigate the thermal behaviours of the metal complexes of the hybrid compounds. [ABSTRACT FROM AUTHOR]

Organic/inorganic hybrid perovskite materials, such as CH3NH3PbX3 (X = I, Br), have attracted the attention of the scientific community due to their excellent properties such as a widely tunable bandgap, high optical absorption coefficient, excellent power conversion efficiency, etc. The exposure of perovskite solar cells and photovoltaic devices to heat can significantly degrade their performance. Therefore, elucidating their temperature-dependent optical properties is essential for performance optimization of perovskite solar cells. We synthesized CH3NH3PbBr3 (MAPbBr3) single crystals through the polymer-controlled nucleation route and investigated the optical properties and molecular structure evolution of them with temperature. Through temperature evolution photoluminescence (PL) spectroscopy, we found that the fluorescence intensity was greatly affected by increasing the temperature, with an asymmetric PL profile suggesting that more captured excitons undergo radiative complexation. The optical photographs showed that the color of MAPbBr3 single crystals faded. Raman spectroscopy revealed that during the heating process, the structure of MAPbBr3 was still preserved at 90 °C since all of the Raman bands were very clear. When the temperature increased to 120 °C, the Raman bands of the internal modes became very weak. On further heating, the inorganic framework on sample's surface started to disintegrate above 210 °C. During the heating process, the PL spectra exhibited significant changes in spectral intensity, peak position and Full Width Half Maximum (FWHM). The PL spectral intensity decreased abruptly with increasing temperature. The peak position was blue shifted with increasing temperature, and the peak shape showed an obvious asymmetry. The FMWH of the PL spectra was gradually broadened with the increase in the temperature, and there was a sharp increase from 270 °C to 300 °C. These variations in the PL spectra with temperature indicate that the optical properties of MAPbBr3 are greatly affected by temperature, which in turn affects the application of MAPbBr3 in fields such as optical devices. These results may be instructive for the application of MAPbBr3. [ABSTRACT FROM AUTHOR]

BODIPY based molecules functionalized with water soluble moieties have been developed and recognized as liable triplet photosensitizers for phototherapeutic applications. In this work, we have prepared BODIPY analogues with dicarboxylic acid groups and bearing iodine or fullerene moieties for efficient intersystem crossing which display far‐red absorption band and high singlet oxygen production both in organic and aqueous media. In this perspective by using similar design the effect of the halogenation of the dyes versus spin converter on the skeleton were compared. The structures of the synthesized BODIPYs and BODIPY‐C60 (6–10) were elucidated by mass, 1H and 13C NMR spectroscopic techniques. Photophysical and photochemical properties of the compounds were examined using UV‐Vis. absorption and fluorescence emission spectrophotometers. The absorption intensities of the trap molecules (DPBF and ADBA) reduced because of singlet oxygen generation in the media. This study may provide useful infrastructure to elucidate the relationship between the use of fullerene (9) or iodine (10) where singlet oxygen quantum yield of 9 and 10 are determined as 0.87 and 0.97 respectively. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive chemistry experiment that involves the synthesis, photophysical and electrochemical characterization of ferrocenylphenyl derivatives. By integrating multiple characterization methods and test approaches, this experiment helps students learn fundamental college chemistry theory, basic laboratory skills, and academic research in the field of organometallics. UV-Visible spectroscopic and electrochemical methods were utilized to study the target compounds and compare the electron-donating and electron-withdrawing effects on the molecular spectrum via a quantitative computation methodology. Furthermore, it stimulates the creation of green chemistry values and sustainable development mindfulness while developing students' scientific research and comprehensive experimental skills. [ABSTRACT FROM AUTHOR]

Dehydrohelicene-based molecules stand out as highly promising scaffolds and captivating chiroptical materials, characterized by their unique chirality. Their quasi-helical π-conjugated molecular architecture, featuring successively ortho-annulated aromatic rings, endows them with remarkable thermal stability and optical properties. Over the past decade, diverse approaches have emerged for synthesizing these scaffolds, reinvigorating this field, with anticipated increased attention in the coming years. This review provides a comprehensive overview of the historical evolution of dehydrohelicene chemistry since the pioneering work of Zander and Franke in 1969 and highlights recent advancements in the synthesis of various molecules incorporating dehydrohelicene motifs. We elucidate the intriguing structural features and optical merits of these molecules, occasionally drawing comparisons with their helicene or circulene analogs to underscore the significance of the bond between the helical termini. [ABSTRACT FROM AUTHOR]

In this work, we report on the synthesis and characterization of six new iridium(III) complexes of the type [Ir(C^N)2(N^N)]+ using 2-phenylpyridine (C1–3) and its fluorinated derivative (C4–6) as cyclometalating ligands (C^N) and R-phenylimidazo(4,5-f)1,10-phenanthroline (R = H, CH3, F) as the ancillary ligand (N^N). These luminescent complexes have been fully characterized through optical and electrochemical studies. In solution, the C4–6 series exhibits quantum yields (Ф) twice as high as the C1–3 series, exceeding 60% in dichloromethane and where 3MLCT/3LLCT and 3LC emissions participate in the phenomenon. These complexes were employed in the active layer of light-emitting electrochemical cells (LECs). Device performance of maximum luminance values of up to 21.7 Lx at 14.7 V were observed for the C2 complex and long lifetimes for the C1–3 series. These values are counterintuitive to the quantum yields observed in solution. Thus, we established that the rigidity of the system and the structure of the solid matrix dramatically affect the electronic properties of the complex. This research contributes to understanding the effects of the modifications in the ancillary and cyclometalating ligands, the photophysics of the complexes, and their performance in LEC devices. [ABSTRACT FROM AUTHOR]

Photochemistry related studies have been driven by with the application of new types of photocatalysis. Lately boron-dipyrromethene (BODIPY) as distinguished chromophore with exceptional photophysical and chemical features has emerged as a viable photosensitizer. Within this context, three new NDI-BODIPY triads (8–10) were synthesized/ characterized and used to investigate the efficiencies of singlet oxygen generation and oxidation of 1,5-dihydroxynapthalene to juglone under visible light. Singlet oxygen generation was determined both via indirect method by using 1,3-diphenylisobenzofuran as trap molecule and from the characteristic 1O2 phosphorescence at 1270 nm. Also, NDI with BODIPY dyes bearing bromine and iodine atoms were shown to be highly active photocatalysts in which the activities are comparable or higher to the readily available commercial systems where 36% (9) and 66% (10) juglone production was achieved under 15 min. This work may emphasize good example of applying NDI-BODIPY based triads as photocatalysts for a series of important organic transformations. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) have attracted a lot of attention over the past decades due to their sharp emission spectrum and color, which can be tuned by changing just the particle size and chromophoric stability. All these advantages of QDs make quantum dot light-emitting diodes (QLEDs) promising candidates for display and light-source applications. This paper demonstrates a large-emitting-area QLED fabricated by a full-solution process. This QLED is composed of indium tin oxide (ITO) as the anode, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT: PSS) as the hole injection layer (HIL), and poly(N,N′-bis-4-butylphenyl-N,N′-bisphenyl)benzidine (poly-TPD) as the hole-transport layer (HTL). The light-emitting layer (EML) is composed of green CdSe/ZnS quantum dots. By applying the ZnO nanoparticles as the electron-injection/transport layer, QLED devices are prepared under a full-solution process. The large-emitting-area QLED exhibits a low turn-on voltage of around 2~3 V, and the International Commission on Illumination (CIE) 1931 coordinate value of the emission spectrum was (0.31, 0.66). The large emitting area and the unique QLED structure of the device make it possible to apply these features to inkjet printing quantum dot light sources and quantum dot display applications. [ABSTRACT FROM AUTHOR]

Optical, photophysical, and thermal properties of poly(paraphenylenevinylene) (PPV) derivatives of various symmetric alkoxyl substituents were studied with UV–vis and photoluminescence spectroscopy. Molar absorptivity coefficients of the symmetric monomers increased compared to that of hydroquinone and its derivatives. The symmetric polymers exhibited photoluminescence quantum yields in the range of 32%–39% and excited‐state lifetimes of 3.01–3.61 ns. The emission energy values for the calculated band gaps were in the range of 2.16–2.12 eV for the symmetric polymers. The photoluminescent characteristics of these compounds may show great potential in improving the emitting layers of electronic devices. The thermal behavior and heat changes of the symmetric dialkyl PPV polymers were monitored by TGA and DSC. Glass transition temperatures (Tg) for these polymers were observed as being in range of 67–108°C. The heat values of the symmetric dialkyl PPV polymers were found to be in range 220.41–599.98 J/g, and the entropy values of symmetric dialkyl PPV polymers were determined to be in range 0.567–1.754 J/ g °C. Highlights: • Symmetric poly(phenylene vinylene) (PPV) derivatives were prepared. • UV–vis spectroscopy was used for optical absorption studies. • Photophysical properties were examined by photoluminescence spectroscopy. • TGA was used for the thermal behavior of symmetric dialkyl PPV polymers. • Heat changes of symmetric dialkyl PPV polymers were investigated by DSC. [ABSTRACT FROM AUTHOR]

Organic/inorganic hybrid perovskite materials, such as CH3NH3PbX3 (X = I, Br), have attracted the attention of the scientific community due to their excellent properties such as a widely tunable bandgap, high optical absorption coefficient, excellent power conversion efficiency, etc. The exposure of perovskite solar cells and photovoltaic devices to heat can significantly degrade their performance. Therefore, elucidating their temperature-dependent optical properties is essential for performance optimization of perovskite solar cells. We synthesized CH3NH3PbBr3 (MAPbBr3) single crystals through the polymer-controlled nucleation route and investigated the optical properties and molecular structure evolution of them with temperature. Through temperature evolution photoluminescence (PL) spectroscopy, we found that the fluorescence intensity was greatly affected by increasing the temperature, with an asymmetric PL profile suggesting that more captured excitons undergo radiative complexation. The optical photographs showed that the color of MAPbBr3 single crystals faded. Raman spectroscopy revealed that during the heating process, the structure of MAPbBr3 was still preserved at 90 °C since all of the Raman bands were very clear. When the temperature increased to 120 °C, the Raman bands of the internal modes became very weak. On further heating, the inorganic framework on sample’s surface started to disintegrate above 210 °C. During the heating process, the PL spectra exhibited significant changes in spectral intensity, peak position and Full Width Half Maximum (FWHM). The PL spectral intensity decreased abruptly with increasing temperature. The peak position was blue shifted with increasing temperature, and the peak shape showed an obvious asymmetry. The FMWH of the PL spectra was gradually broadened with the increase in the temperature, and there was a sharp increase from 270 °C to 300 °C. These variations in the PL spectra with temperature indicate that the optical properties of MAPbBr3 are greatly affected by temperature, which in turn affects the application of MAPbBr3 in fields such as optical devices. These results may be instructive for the application of MAPbBr3.

Co-catalysts decorations provide unique opportunity in promoting the photocatalytic water splitting performance of graphite carbon nitride (g-C3N4) system, while mechanistic understanding of this complex catalytic network remains elusive. Here, taking the single-atom-based photocatalysts (M1-g-C3N4) as an unprecedented simplified model system, we theoretically tracked the photocatalytic kinetics for a comprehensive understanding of the photocatalytic process and afforded the descriptor αS1-T1/αT1-S0 (ratio of the extent of S1-T1 and T1-S0 state mixing) and ΔGH* (hydrogen adsorpti on free energy) for rational screening of photocatalysts. The targeted Fe1-g-C3N4 yields an excellent H2 evolution rate (ca. 3.2 ⋅mmol⋅gcat -1 ⋅h-1 under full arc), two order of magnitude improvement relative to pristine g-C3N4 counterpart and also outperforms other representative 3d-transition-metal-based photocatalysts. This work presents a comprehensive understanding of the essential role of isolated atomic sites in the photocatalytic course and sheds light on the design of photocatalysts from both photophysical and photochemical aspects. [ABSTRACT FROM AUTHOR]

Pyrazole-containing compounds represent one of the most influential families of N-heterocycles due to their proven applicability and versatility as synthetic intermediates in preparing relevant chemicals in biological, physical-chemical, material science, and industrial fields. Therefore, synthesizing structurally diverse pyrazole derivatives is highly desirable, and various researchers continue to focus on preparing this functional scaffold and finding new and improved applications; this review highlights some of the most recent and strategic examples regarding the synthesis and properties of different pyrazole derivatives, mainly reported from 2017–present. The discussion involves strategically functionalized rings (i.e., amines, carbaldehydes, halides, etc.) and their use in forming various fused systems, predominantly bicyclic cores with 5:6 fusion taking advantage of our experience in this field and the more recent investigations of our research group.

Coumarin based heterocyclic chalcone (E)-3-(3-(1-allyl-1H-indol-3-yl) acryloyl)-7-(diethylamino)-2H-chromen-2-one (AADC) was synthesized by the multi-steps synthesis. The structure of the AADC was established by the spectroscopic technics and purity of the AADC was confirmed by the elemental analysis. Physicochemical parameters of the AADC in ten different solvents such as molar absorption coefficient, transition dipole moments, stokes shift, oscillator strength and fluorescence quantum yield were calculated. Interaction of the AADC chromophore with cationic CATB and anionic SDS surfactants were determined by using the fluorescence spectroscopy techniques. It was observed that band fluorescence spectrum intensity increases with increasing the concentration of the surfactants. This suggests that strong interaction occurs between AADC with surfactants and this interaction arise from electrostatic forces. So, AADC chromophore could be used as analysis to define the CMC of the surfactants. [ABSTRACT FROM AUTHOR]

Despite a significant focus on the photochemical and photoelectrical mechanisms underlying photobiomodulation (PBM), its complex functions are yet to be fully elucidated. To date, there has been limited attention to the photophysical aspects of PBM. One effect of photobiomodulation relates to the non-visual phototransduction pathway, which involves mechanotransduction and modulation to cytoskeletal structures, biophotonic signaling, and micro-oscillatory cellular interactions. Herein, we propose a number of mechanisms of PBM that do not depend on cytochrome c oxidase. These include the photophysical aspects of PBM and the interactions with biophotons and mechanotransductive processes. These hypotheses are contingent on the effect of light on ion channels and the cytoskeleton, the production of biophotons, and the properties of light and biological molecules. Specifically, the processes we review are supported by the resonant recognition model (RRM). This previous research demonstrated that protein micro-oscillations act as a signature of their function that can be activated by resonant wavelengths of light. We extend this work by exploring the local oscillatory interactions of proteins and light because they may affect global body circuits and could explain the observed effect of PBM on neuro-cortical electroencephalogram (EEG) oscillations. In particular, since dysrhythmic gamma oscillations are associated with neurodegenerative diseases and pain syndromes, including migraine with aura and fibromyalgia, we suggest that transcranial PBM should target diseases where patients are affected by impaired neural oscillations and aberrant brain wave patterns. This review also highlights examples of disorders potentially treatable with precise wavelengths of light by mimicking protein activity in other tissues, such as the liver, with, for example, Crigler-Najjar syndrome and conditions involving the dysregulation of the cytoskeleton. PBM as a novel therapeutic modality may thus behave as "precision medicine" for the treatment of various neurological diseases and other morbidities. The perspectives presented herein offer a new understanding of the photophysical effects of PBM, which is important when considering the relevance of PBM therapy (PBMt) in clinical applications, including the treatment of diseases and the optimization of health outcomes and performance. [ABSTRACT FROM AUTHOR]

An indole-related molecules have been considered as the potential fluorescent probes for biological and electrochemical sensing. However, most of the indole probes have been usually used in a single detection mode. Indolium probes that enable accurate detection in complex environments are rarely reported. Here, four novel indole derivatives including the phenyl group substituted with different functional moieties were designed on the basis of the donor-π-acceptor (D-π-A) concept. These derivatives exhibit positive solvatochromism owing to their varied molecular conformations upon contacting to various solvents and the different HOMO-LUMO gaps caused by the difference in electronic push-pull capability of the substituents. Their solid-state fluorescence emissions and multiple chromisms are observed due to the inherent twisted geometries and aggregation modes. In addition, these derivatives show dramatic color and fluorescence responses due to the protonation of the nitrogen and oxygen containing groups, and thus novel colorimetric pH sensors, fluorescent papers and logic gates have been designed. [ABSTRACT FROM AUTHOR]

Two new BODIPY-fluorene-fullerene (3) and BODIPY-fluorene-BODIPY (4) conjugates were designed, synthesized, and characterized for the first time. The structural properties of compounds were investigated with elemental analysis, mass, 1H, and 13C NMR techniques. Absorption and fluorescence spectroscopy were used to examine the photophysical (absorption and emission profiles, fluorescence quantum yields, and lifetimes) and photochemical (formation of singlet oxygen (1O2)) properties. It was observed that the novel compounds (3) and (4) showed high molar extinction coefficients and good 1O2 quantum yields. 1O2 formation ability of the BODIPY-fluorene-fullerene conjugate (3) was more efficient than that of the BODIPY-fluorene-BODIPY conjugate (4). Furthermore, photosensitization ability of both conjugate systems was more remarkable than some commonly used BODIPY based photosensitizers. The data presented in this work indicate that these two novel systems are effective 1O2 photosensitizers that might be used for various areas of applications such as photodynamic therapy and photocatalysis. [ABSTRACT FROM AUTHOR]

A series of 2,6-di(pyrazine-2-yl)pyridine (dppy) ligands 1 - 4 of varying substituents of different electronic nature (-NMe 2 , -OMe,-Me, and -Cl) in the 4-position of the pyridine moiety has been designed and synthesized to study the binding behavior of the dppy ligands towards Bovine Serum Albumin (BSA), a low-cost serum albumin protein. The interaction between ligands 1-4 and BSA has been studied using UV-Visible and fluorescence spectroscopy and molecular docking studies. The fluorescence of BSA was found to be quenched in the presence of all the ligands 1-4 , in which ligand 1 , having the most electron donating group NMe 2, exhibits the maximum binding affinity towards BSA. The interaction between ligands 1-4 and BSA was found to be static and spontaneous in nature. Further, the effect of substituents on the photophysical, thermal, and electrochemical properties of the dppy ligands has also been studied. Structure optimization and theoretical studies have been conducted to acquire a deeper understanding of the ligands' nature. The trend of the energy gaps between the HOMO and the LUMO of the synthesized ligands 1-4 , calculated from the electrochemical analysis, has been reflected in the theoretical observations. Moreover, the ligands were also tested against different bacterial and fungal strains, and ligands containing electron-donating-NMe 2 and-OMe groups were quite active in both bacterial and fungal studies. The ligand 4 , having the-CH 3 group, showed moderate activity against fungal strains.

We designed the new xanthene dyes by introducing the donor and acceptor group of electrons in the 5' position of the carboxyphenyl ring. These synthesized dye molecules were identified using spectroscopy. And the photophysical studies, such as solvent optimization, were further explored before and after photodegradation of all synthesized dye compounds in both states (solution and solid). The resulting dyed modacrylic fabrics and measured their K/S values, reflectance (%), solid UV absorbance, and photoluminescence. All compounds are plotted on a chromaticity map in the pink region. During photodegradation, the stability of the molecule depends on the effect of the functional groups (donor to acceptor). In this case, ln[C/C0] (%) became the decreasing sequence from an electron donor to acceptor, as the electrons followed from the donation function group to the carboxylic function group. Therefore, the electron-accepting group dyes decompose rapidly during ultraviolet radiation. [ABSTRACT FROM AUTHOR]

In this study, compounds (E)-4-((5-bromo-2-hydroxy-3-methoxybenzylidene)amino)-N-(pyridin-2-yl)benzenesul-fonamide 1, (E)-4-((5-bromo-2-(3,4-dicyanophenoxy)-3-methoxybenzylidene)amino)-N-(pyridin-2-yl)benzenesulfonamide 2 and, complex 2(3),9(10),16(17),23(24)-tetra-[(E)-4-((5-bromo-3-methoxy-2-(λ1-oxidanyl)benzylidene)amino)-N-(pyridine-2-yl)benzenesulfonamide]phthalocyaninato zinc(II) 3 were synthesized for the first time. Their structures (1 –3) were characterized by spectroscopic methods such as FTIR, 1H NMR,13C NMR, UV–vis, MALDI-TOF mass spectra and elemental analysis. The spectroscopic, aggregation, photophysical and photochemical properties of zinc(II) phthalocyanine 3 in dimethyl sulfoxide were investigated and the effects on the above-mentioned properties were reported as a result of the presence of benzenesulfonamide derivatives containing different bioactive groups, in their peripheral positions. In addition, its above-mentioned properties were also reported by comparing different species with those of their substituted and/or unsubstituted counterparts. The zinc(II) phthalocyanine 3 can be a potential photosensitizer candidate in photodynamic therapy, which is an effective alternative therapy in cancer treatment, due to its good solubility in commonly known solvents and monomeric species, as well as its adequate and favorable fluorescence, singlet oxygen production and photostability. [ABSTRACT FROM AUTHOR]

[Display omitted] • New series of metallomacrocyclic complexes holding functionalized linkers. • Ability to act as single source precursors for the synthesis of MS nanoparticle. • HOMO-LUMO band gaps falls in the range of 1.19–1.33 eV for some of the complexes. • Potential molecular probes for optical detection of Pb(II), Cd(II) and Hg(II) ions. Two secondary diamines viz. N,N' -bis{3-(p -methoxybenzylamino)propyl}piperazine (H 2 L1) and N,N' -bis{3-(p-chlorobenzylamino)propyl}piperazine (H 2 L2) holding N,N' -bispropylpiperazine linkers have been prepared and subsequently used to derive a new series of N,N' -bis(3-dithiocarbamatopropyl) piperazine bridged metallomacrocyclic complexes [M(II) 2 - µ2 -bis-{(κ2S,S -S 2 CN(R)C 3 H 6) 2 piperazine}] wherein R = p -methoxybenzyl, M = Ni(II) 1, Cu(II) 2, Zn(II) 3; R = p -chlorobenzyl, M = Ni(II) 4, Cu(II) 5, Zn(II) 6. The formation and purity of all the metallomacrocyclic dithiocarbamate complexes were verified by microanalysis and standard methods such as HRMS, NMR, IR and UV–Visible absorption spectroscopy and corroborated by density functional theory calculations. The experimental (magnetic susceptibility and UV–Visible) and theoretical calculations suggest a square planar/distorted square planar environment around nickel(II)/copper(II) and tetrahedral/distorted tetrahedral environment around zinc(II) centres in 1–6. Thermogravimetric study was carried out on 1–6 to study their thermal stability and degradation behaviour. Notably, TG curves of compounds 2, 3 and 5 gave a stable residual mass corresponding to corresponding metal sulphides (MS). Notably, the calculated HOMO-LUMO gaps (1.19–1.33 eV) for Cu(II)-dithiocarbamate 2 and 5 indicates their semiconducting nature. The potentials of these metallomacrocycles as a molecular probe for optical sensing of environmentally hazardous heavy metal ions ca Pb(II), Cd(II) and Hg(II) were further examined by using UV–Visible and fluorescence spectroscopies. [ABSTRACT FROM AUTHOR]

Pyrazole-containing compounds represent one of the most influential families of N-heterocycles due to their proven applicability and versatility as synthetic intermediates in preparing relevant chemicals in biological, physical-chemical, material science, and industrial fields. Therefore, synthesizing structurally diverse pyrazole derivatives is highly desirable, and various researchers continue to focus on preparing this functional scaffold and finding new and improved applications; this review highlights some of the most recent and strategic examples regarding the synthesis and properties of different pyrazole derivatives, mainly reported from 2017–present. The discussion involves strategically functionalized rings (i.e., amines, carbaldehydes, halides, etc.) and their use in forming various fused systems, predominantly bicyclic cores with 5:6 fusion taking advantage of our experience in this field and the more recent investigations of our research group. [ABSTRACT FROM AUTHOR]

2(3),9(10),16(17),23(24)-tetrakis-2,6-dimethoxyphenoxy substituted magnesium (II) phthalocyanine, which has very good solubility in polar and non-polar solvents and does not aggregate, was synthesized. Its structure was characterized by spectroscopic methods such as elemental analysis, UV-vis, FT-IR, MALDI-TOF mass and 1H NMR. It has very good solubility in polar aprotic solvents such as dimethyl sulfoxide, N, N- Dimethylformamide, tetrahydrofuran, dichloromethane, and non-polar solvents such as toluene, chloroform. Its aggregation properties have been studied both in the solvents mentioned above and in N, N- Dimethylformamide at different concentrations. Its photophysical properties were determined in N, N-dimethyl formamide. The effects of the nature and presence of 2,6-dimethoxyphenoxy group, which is an antioxidant derivative, on the phthalocyanine skeleton on the spectroscopic and photophysical properties were investigated by comparing it with unsubstituted magnesium (II) phthalocyanine. It can be a good nominee for various technological applications in that it does not aggregate and has good solubility in polar and non-polar solvents, as well as better and favorable fluorescence properties than its analog in the previous study.

New compounds 3,6-bis(2-azidoethoxy)phthalonitrile and 1,4,8,11,15,18,22,25-octakis-(2-azidoethoxy) phthalocyaninato zinc(II) were synthesized and characterized by general spectroscopic methods such as UV-Vis, FT-IR, 1H NMR and mass spectrometry. Moreover, photosensitizer ability for photodynamic therapy applications; singlet oxygen photosensitizer, photodegradation and fluorescence abilities of 14,8,11,15,18,22,25-octakis-(2-azidoethoxy) phthalocyaninato zinc(II) molecule were investigated and reported. [ABSTRACT FROM AUTHOR]

Despite a significant focus on the photochemical and photoelectrical mechanisms underlying photobiomodulation (PBM), its complex functions are yet to be fully elucidated. To date, there has been limited attention to the photophysical aspects of PBM. One effect of photobiomodulation relates to the non-visual phototransduction pathway, which involves mechanotransduction and modulation to cytoskeletal structures, biophotonic signaling, and micro-oscillatory cellular interactions. Herein, we propose a number of mechanisms of PBM that do not depend on cytochrome c oxidase. These include the photophysical aspects of PBM and the interactions with biophotons and mechanotransductive processes. These hypotheses are contingent on the effect of light on ion channels and the cytoskeleton, the production of biophotons, and the properties of light and biological molecules. Specifically, the processes we review are supported by the resonant recognition model (RRM). This previous research demonstrated that protein micro-oscillations act as a signature of their function that can be activated by resonant wavelengths of light. We extend this work by exploring the local oscillatory interactions of proteins and light because they may affect global body circuits and could explain the observed effect of PBM on neuro-cortical electroencephalogram (EEG) oscillations. In particular, since dysrhythmic gamma oscillations are associated with neurodegenerative diseases and pain syndromes, including migraine with aura and fibromyalgia, we suggest that transcranial PBM should target diseases where patients are affected by impaired neural oscillations and aberrant brain wave patterns. This review also highlights examples of disorders potentially treatable with precise wavelengths of light by mimicking protein activity in other tissues, such as the liver, with, for example, Crigler-Najjar syndrome and conditions involving the dysregulation of the cytoskeleton. PBM as a novel therapeutic modality may thus behave as “precision medicine” for the treatment of various neurological diseases and other morbidities. The perspectives presented herein offer a new understanding of the photophysical effects of PBM, which is important when considering the relevance of PBM therapy (PBMt) in clinical applications, including the treatment of diseases and the optimization of health outcomes and performance.

Synthesis of the Zn, Mg, and LuOAc phthalocyanines (Pcs) containing sterically hindered 2,6-di-(tert-butyl)-4-methylphenol group were successfully achieved by the cyclotetramerization of the 4-[2,6-di-(tert-butyl)-4-methylphenoxy]phthalonitrile. All compounds were fully characterized by 1H and 13C NMR, infrared, elemental analysis, UV–Vis, and MALDI-TOF spectral data. The photo-physicochemical properties of the targeted molecules include fluorescence quantum yields, lifetimes, singlet oxygen generation, and photodegradation quantum yields were recorded in dimethyl sulfoxide. [ABSTRACT FROM AUTHOR]

• Four targeting fluorescent 5-substituted-benzothiazole conjugates (3a, 3b, 6a, and 6b) were synthesized. • The photophysical characteristics of the synthesized conjugates, as well as measurements of absorbance and fluorescence maxima in diverse organic solvents. • The conjugates' cytotoxicity was evaluated across different anticancer cell lines. • The inhibitory activity of these conjugates against VEGFR-2 was assessed using an antiphosphotyrosine antibody. • The synthesized 5-substituted-benzothiazole conjugates 3a, 3b, and 6a were stimulated using molecular docking. • The ADME study was performed and showed that conjugates 3b and 6b exhibited enhanced lipophilicity and reduced solubility. Four targeting fluorescent 2-(N , N -dimethyl/diphenyl-aminophenyl)-5-substituted-benzothiazole conjugates 3a , 3b , 6a and 6b were synthesized. Insight into the photophysical characteristics of the synthesized conjugates, as well as measurements of absorbance and fluorescence maxima in diverse organic solvents, showed conjugate 3b ranged from 302 to 324 nm, whereas the fluorescence maxima ranged from 312 nm (CH 2 Cl 2) to 465 nm. The conjugates' cytotoxicity was evaluated across anticancer cell lines, and the inhibitory action of these conjugates against VEGFR-2 was assessed using an antiphosphotyrosine antibody, with 3b and 6b conjugates showing potent cytotoxic activity against MCF-7 cells with IC 50 values of 7.06 ± 0.29 and 8.82 ± 0.37 μM, respectively. Meanwhile, conjugate 6b had the greatest potency of the conjugates for VEGFR-2 inhibition, with an IC 50 of 0.23 ± 0.20 μM. Though the binding's interactions were stimulated using molecular docking, A higher binding score and a variety of interaction types for conjugate 3b , temporarily, indicated a stronger interaction. Moreover, the ADME study was performed and showed that conjugates 3b and 6b exhibited enhanced lipophilicity and reduced solubility, which may influence their pharmacokinetic behavior. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Keggin polyoxometalate (POM)-sulfadiazine porous material has been prepared. • The hybrid compound (A) showed irreversible redox processes at some potentials. • The structure of the hybrid material contains solvent accessible voids. • Thermal properties of the hybrid compound (A) were investigated by TGA/DTA. • The loss of the adsorbed water molecules on the hybrid compound (A) starts at 28 °C. In this paper, a new supramolecular assembled Keggin polyoxometalate (POM) based organic-inorganic porous material (A; [HSiMo 12 O 40 ].3[C 10 H 11 N 4 O 2 S].48H 2 O) containing the compound sulfadiazine (SZD) has been prepared and its molecular structure was determined. To characterize the hybrid compound (A), X-ray crystallography, MALDI-TOF, UV–Vis, photoluminescence and FTIR methods were used. The electrochemical properties of the Keggin POM, SZD and porous hybrid (A) compounds were investigated in the −1.8 – 1.8 V range and the redox processes at some potentials of the hybrid compound (A) are irreversible at 250 and 500 mV/s scan rates. Thermal stability properties of the hybrid compound (A) were investigated by the TGA/DTA instruments. The loss of the adsorbed water molecules on the hybrid compound (A) starts at 28 °C temperature. Crystal structure of the hybrid compound contains a Keggin type polyoxometalate [HSiMo 12 O 40 ]3− and three monoprotonated sulfadiazinium (HSZD)+ cations. In the structure of the hybrid material, there are solvent accessible voids along a axis filled with water molecule. [ABSTRACT FROM AUTHOR]

• A novel tetraphenylene dimer was prepared. • Tetraphenylene dimer exhibited the turn-off fluorescence response to Hg2+. • Hg2+-induced mesomorphic transition was observed. • Hg2+-induced gel transition was distinguished. • The kind of triple responses for supramolecular material were firstly presented. The metal-coordination self-assemble system played an important role on constructing novel supramolecular smart-response materials. Although the single and double-response materials based on metal-induced self-assembly had been studied extensively, the triple responses for this kind of supramolecular material was seldom reported. In this work, the first metal-induced self-assemble system with triple responses on photophysical, liquid crystalline and gel properties was presented based on Hg2+-coordination tetraphenylene dimer (Bis-TPE). Bis-TPE was prepared by bridging two alkyl-substituted tetraphenylene with amido chain. It possessed the fluorescence response from the strong emission for Bis-TPE to the faint emission for Bis-TPE -Hg2+ complex. The self-assemble mechanism of Bis-TPE -Hg2+ was clarified as that Hg2+ was located in the cavity of the amido-ether chain of Bis-TPE. The Hg2+-induced mesomorphic transition was also observed from smectic mesophase for Bis-TPE to hexagonal columnar mesophase for Bis-TPE -Hg2+ complex. The unique Hg2+-induced gel transition was further distinguished from low-order spherical morphology for Bis-TPE to high-order fibrous morphology for Bis-TPE -Hg2+ complex. The maximum fluorescence wavelength exhibited the giant shift from 494 nm for Bis-TPE in gel to 606 nm for Bis-TPE -Hg2+ in gel. This kind of triple responses on photophysical, liquid crystalline and gel properties for metal-coordination self-assemble system was described for the first time, affording a new idea on design of new multiple-response materials with unique properties. [ABSTRACT FROM AUTHOR]

2(3),9(10),16(17),23(24)-tetrakis-2,6-dimethoxyphenoxy substituted magnesium (II) phthalocyanine, which has very good solubility in polar and non-polar solvents and does not aggregate, was synthesized. Its structure was characterized by spectroscopic methods such as elemental analysis, UV-vis, FT-IR, MALDI-TOF mass and 1H NMR. It has very good solubility in polar aprotic solvents such as dimethyl sulfoxide, N, N- Dimethylformamide, tetrahydrofuran, dichloromethane, and non-polar solvents such as toluene, chloroform. Its aggregation properties have been studied both in the solvents mentioned above and in N, N- Dimethylformamide at different concentrations. Its photophysical properties were determined in N, N-dimethyl formamide. The effects of the nature and presence of 2,6-dimethoxyphenoxy group, which is an antioxidant derivative, on the phthalocyanine skeleton on the spectroscopic and photophysical properties were investigated by comparing it with unsubstituted magnesium (II) phthalocyanine. It can be a good nominee for various technological applications in that it does not aggregate and has good solubility in polar and non-polar solvents, as well as better and favorable fluorescence properties than its analog in the previous study. [ABSTRACT FROM AUTHOR]

Two new quinazoline derivatives (2a and 2b) were successfully synthesized in this work using the condensation technique in excellent yields. Using spectroscopic techniques and elemental analyses, the compounds were completely characterized. Density functional theory (DFT) computations have been used to examine the title compound's reactive characteristics. Chemical reactivity was predicted using local reactive descriptors and molecule electrostatic potential. Additionally, Time dependent DFT (TD-DFT) simulations were used to examine the impact of solvents on the photophysical characteristics. The affinity of compounds 2a and 2b for human serum albumin (HSA) was further explored using several electronic spectroscopies. Through static mechanisms, both compounds reduce the intrinsic fluorescence of HSA. It is determined that the HSA-2b complex's binding constant is significantly greater than the HSA-2a complex. The fluorescence spectrum measurements proved that the HSA underwent structural changes after interaction with these compounds. It was demonstrated by site marker competitive displacement studies that compounds 2a and 2b preferred to bind to site I in HSA subdomain IIA. Additionally, synchronised fluorescence spectra were utilized to analyze how HSA's conformation changed after interacting with various substances. The molecular docking investigations of these compounds with the three critical HSA binding sites, comprising subdomains IIA, IIIA, and IB, further confirmed the experimental findings. The significant contact between the investigated compounds and HSA was supported by the docking simulations.Communicated by Ramaswamy H. Sarma.

The scientific community has shown a growing interest in relating to the lanthanide based luminescent materials and it has made an effort to develop them. Among these several luminescent materials, we have proposed to developed (Y,Gd)F3 nanophosphors doped with distinct of Eu3+ concentrations using modified hydrothermal process. The effect of co-doping of rare earth activators to the host lattice structure and morphology are investigated using different analytical techniques. The diffuse reflectance spectra reveal a tuning of optical band gap due to substitutions. From the extensive XPS analysis, Gd and Eu are found to be in a stable ionic state of +3 which is replacing Y3+ in YF3 host. Photoluminescence emission spectra of the nanophosphors are excited by near ultraviolet (UV, 393 nm) excitation. From photoluminescence study, the intensity variation is observed for emission peak at 591 nm and fluorescence quenching occurs at higher doping level. This effect subsequently explained on the frame work of local symmetry and nonradiative transfer among multipole-multipole interaction. At 393 nm excitation Eu3+ (2, 3, 5, 7, 10 at %) doped (Y, Gd) F3 show CIE chromaticity coordinates shifted to red regions with increase in Eu doping levels. Because of the longer decay time these phosphors can be used for bio-labeling and other similar applications. [ABSTRACT FROM AUTHOR]

Cadmium selenide quantum dots (CdSe QDs) were synthesized in aqueous solution using a dual-stabiliser-capped. The photoluminescent and electrochemilumiscent properties were modulated with the change in the capping composition. [Display omitted] • CdSe quantum dots stable and soluble in aqueous media were synthesised. • 3-Mercaptopropionic and 3-morpholinoethanesulfonic acids were used as dual-stabiliser. • The surface state is responsible for the different behavior of fluorescence and electrochemiluminescence. • The intensity of the electrochemiluminescence can be modulated by changes in the composition of the dual-stabiliser capping of quantum dots. In order to obtain an emitter nanoprobe for applications in aqueous solutions, we synthesised quantum dots of CdSe (CdSe QDs) in aqueous solutions, which were stabilised with 3-morpholinoethanesulfonic (MES) and 3-mercaptopropionic (MPA) acids. Comprehensive photophysical and electrochemical studies were carried out in order to determine the optimum MPA:MES ratio that produces the highest electrogenerated chemiluminescence (ECL) intensity. We found that the variation between the relationship of MPA and MES directly affected the surface, the size and properties of the CdSe QDs. Characteristic parameters of CdSe QDs were determined by conventional photophysical and electrochemical techniques, where an excellent correlation between the two methods was found. In addition, diameter, quantum yield (ϕ NC), bandgap (E g) and lifetime of CdSe QDs were determined. It was also observed that as the proportion of MPA in the capping increased, the ϕ NC increased, and that an increase in the proportion of MES in the capping increased the intensity of ECL. The surface state of quantum dots is responsible for the difference in the behaviour between fluorescence and electrochemiluminescence properties. These results allowed us to infer that the choice of dual-stabiliser will depend on the applications of the resulting quantum dots as nanoprobe emitters. [ABSTRACT FROM AUTHOR]

Three mononuclear Nd(III) complexes [Nd(HL1)2(NO3)3] (1, HL1=2-methoxy-6-[(E)-(phenylimino)methyl]phenol), [Nd(HL2)3(NO3)3] (2, HL2=5-methoxy-2-[(E)-(phenylimino)methyl]phenol) and [Nd(HL3)2(NO3)3]·CH3OH (3, HL3=2-methoxy-6-{(E)-[(2-methoxyphenyl)imino]methyl}phenol) were prepared in a 1:3 ratio (M:L) in methanol. The effect of the ligand substituents and their positions (meta versus para) on the electronic and photophysical properties of the complexes is demonstrated. Single-crystal X-ray diffraction studies show that HL1 and HL3 coordinate bidentate via the phenolate and methoxy oxygens, while HL2 is bound monodentately through the phenolate oxygen, with the coordination environment completed by three η2-chelated nitrates. The significant differences observed in the coordination chemistry of the three Nd(III) complexes provides the opportunity for biological application investigations. [ABSTRACT FROM AUTHOR]

Three new 2-component unsubstituted (4P), diiodo- (5P), and dibromo- (6P) distyryl-BODIPY-bridged cyclotriphosphazene dimers were designed and synthesized. The newly synthesized BODIPY-cyclotriphosphazene systems were characterized by ¹H, 13C, and 31P NMR spectroscopy. The photophysical properties of the distryl-BODIPYs (4-6) and BODIPY-cyclotriphosphazene dyads (4P-6P) were studied by UV-Vis absorption and fluorescence emission spectroscopy. In these derivatives, the bino-type cyclotriphosphazene derivative bearing unsubstituted BODIPY unit 4 P exhibited high fluorescence and no singlet oxygen generation due to the lack of spin converter. The attachment of heavy atoms (iodine and bromine) enabled the production of singlet oxygen. The bino-type BODIPY-cyclotriphosphazenes (5P and 6P) were also used as triplet photosensitizers in the photooxidation of 1,3-diphenylisobenzofuran to endoperoxide via generation of the singlet oxygen in dichloromethane. The singlet oxygen production of these compounds was also investigated via a direct method and produced a singlet oxygen phosphorescence peak at 1270 nm. [ABSTRACT FROM AUTHOR]

In the present work, pyrene-boron-dipyrromethene (BODIPY)-substituted novel water-soluble cyclotriphosphazene derivatives (6 and 7) were synthesized by click reactions between a cyclotriphosphazene derivative with a hydrophilic glycol side group (2) and BODIPYs (4 and 5). All of the new compounds (2, 6, and 7) were characterized by Fourier-transform infrared and nuclear magnetic resonance spectroscopy, as well as mass spectrometry and elemental analysis. The photophysical properties of the BODIPY-substituted cyclotriphosphazenes (6 and 7) were investigated by UV-Vis and fluorescence emission spectroscopy in water and water/solvent mixtures. It was found that the target compounds were soluble in water and could be potential candidates as water-soluble fluorescent dyes for the desired applications. [ABSTRACT FROM AUTHOR]