Benzaldehyde Molecules Research Articles

A novel dual-site fluorescent probe for the one-step detection of Cys and SO2 in living cells

BackgroundCysteine (Cys) is the major intracellular thiol and plays a key role in human pathology. Furthermore, endogenous sulfur dioxide (SO2) is produced in mammals. Abnormal levels of SO2 are commonly associated with a variety of respiratory, cardiovascular, and neurological diseases. Therefore, given their important role in life activities, it is significant to construct a fluorescent probe that can detection between Cys and SO2. ResultsWe have designed and synthesized a two-site fluorescent probe CUM with coumarin derivative and benzaldehyde molecules, which can detect and differentiate between Cys and SO2 through dual excitation wavelengths. Its carbon-carbon double bond reacts with Cys and undergoes a nucleophilic reaction, emitting green fluorescence at 520 nm, while SO32− reacts with benzaldehyde molecules in the probe CUM and undergoes a blue fluorescence at 460 nm. SO32− reacts with the benzaldehyde molecule of probe CUM and fluoresces blue at 460 nm. Thus, the probe CUM with two reaction sites can distinguish between Cys and SO2 and shows good selectivity and fast reaction speed. In addition, we successfully utilized probe CUM to image Cys and SO2 in human breast cancer cells (MDA-MB-231). SignificanceThis work provides an effective method for the molecular design of coumarin-based fluorescent probes. Probe CUM as a promising and reliable tool for the meticulous discrimination and quantification of Cys and SO2 in diverse biological matrices, thereby opening up new avenues for various biological systems.

Mechanism of Electrocatalytic H2 Evolution, Carbonyl Hydrogenation, and Carbon-Carbon Coupling on Cu.

Aqueous-phase electrocatalytic hydrogenation of benzaldehyde on Cu leads not only to benzyl alcohol (the carbonyl hydrogenation product), but Cu also catalyzes carbon-carbon coupling to hydrobenzoin. In the absence of an organic substrate, H2 evolution proceeds via the Volmer-Tafel mechanism on Cu/C, with the Tafel step being rate-determining. In the presence of benzaldehyde, the catalyst surface is primarily covered with the organic substrate, while H* coverage is low. Mechanistically, the first H addition to the carbonyl O of an adsorbed benzaldehyde molecule leads to a surface-bound hydroxy intermediate. The hydroxy intermediate then undergoes a second and rate-determining H addition to its α-C to form benzyl alcohol. The H additions occur predominantly via the proton-coupled electron transfer mechanism. In a parallel reaction, the radical α-C of the hydroxy intermediate attacks the electrophilic carbonyl C of a physisorbed benzaldehyde molecule to form the C-C bond, which is rate-determining. The C-C coupling is accompanied by the protonation of the formed alkoxy radical intermediate, coupled with electron transfer from the surface of Cu, to form hydrobenzoin.

Doped STR@mSiO2-GO nanocomposite coatings for enhanced anticorrosion protection of copper

This study presents an innovative approach to improve the anticorrosion performance of epoxy coatings by incorporating 2-hydroxy-5-((4-(hydroxymethyl)-1H-1,2,3-triazol-1-yl)methyl) benzaldehyde (STR) molecules into a matrix of mesoporous silica (mSiO2) grafted onto graphene oxide (GO) sheets. The resulting porous hybrid composites (STR@mSiO2-GO) underwent thorough characterization via scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Corrosion resistance was assessed using salt spray testing and electrochemical impedance spectroscopy (EIS). The results show the superior corrosion resistance of the polymer nanocomposite coatings compared to pure epoxy coatings. Notably, incorporating 10 wt% TiO2 into the mSiO2-GO epoxy matrix significantly increased the corrosion protection efficacy from 74.48 % to 99.85 %. This enhancement is attributed to synergies between TiO2 nanoparticles and the mSiO2-GO matrix, leading to a hydrophobic polymeric nanocomposite coating that significantly boosts corrosion resistance. This study introduces an innovative approach for developing high-performance epoxy coatings with improved anti-corrosion properties, showcasing promising strides in corrosion protection technology.

A detailed theoretical investigation on intramolecular charge transfer mechanism of primary, secondary, and tertiary p-amino substituted benzaldehyde

This article reports a detailed theoretical investigation on dual fluorescence properties of p-amino substituted benzaldehyde molecules by taking specifically p-N,N-dimethylaminobenzaldehyde (3° PABA), p-N-methylaminobenzaldehyde (2° PABA), and p-aminobenzaldehyde (1° PABA) molecules. The calculations are performed in gas phase as well as in butanol (BuOH) and dichloromethane (DCM) solvents. Twisted intramolecular charge transfer emission property is particularly looked at by scanning the potential energy curves as a function of -NR2 (R = H/CH3) rotation (twisting) angle. The results suggest that there are dual emission possibilities for 3° and 2° PABA molecules. Experimental validation is available for the former but not for the latter. 1° PABA, on the other hand, does not show any possibility of dual fluorescence except in BuOH. The theoretical absorption and emission spectra are also calculated and compared with experiment where it is available, and they are in close correlation. Excited state molecular dynamics simulations show that for 3° PABA, the molecule reaches to the 90° twisting angle and stays there with a probability higher than the same probability for 2° PABA. 1° PABA, on the other hand, had showed variations in the twisting angle from 0° to above 100°, but no evidence of this molecule to have considerable lifetime at 90° twisting angle.

Nitrogen-doped carbon confined cobalt nanoparticles as the steric acid-base multifunctional catalysts for Knoevenagel condensation

Nitrogen-doped carbon confined cobalt nanoparticles (Co-N-C) were synthesized through multi-step pyrolysis method. The Co-N-C samples exhibit excellent catalytic performance in the Knoevenagel reaction of benzaldehyde and malononitrile, of which the yield can be as high as 93.7% within 2.5 min with outstanding stability and recyclability. The catalytic performance may be primarily ascribed to the richness in nitrogen and cobalt in the form of the solid Frustrated Lewis Pair (FLP), i.e. the Co ion acts as a Lewis acid site to activate the carbonyl oxygen of benzaldehyde molecules, and nitrogen in carbon acts as a Lewis base site to activate the methylene hydrogen of malononitrile. From the perspective of intrinsic catalytic activity, variations in catalytic properties are attributed to the electron density distribution on the surface of the catalyst.

The predicted value of potential barrier to internal rotation of benzaldehyde: Is there a conflict between the theory and the experiment or not?

The ratio of potential barrier heights for the internal rotation of benzaldehyde molecule calculated by quantum mechanical methods and determined experimentally from UV spectra has been discussed. Based on the joint analysis of the results of ab initio MP2/6-311G** calculations of normal vibrations of benzaldehyde in the ground state and the results of interpretation of the observed UV spectra of the compound, possible approximations for a correct description of the hindered internal rotation of the aldehyde group have been considered. The two-dimensional model including the kinematic interaction between torsion and out-of-plane deformation of aldehyde group has been established as more efficient for the correct description of the hindered rotation in benzaldehyde.

Noble metal (Pt or Pd)-decorated atomically thin MoS2 as a promising material for sensing colorectal cancer biomarkers through exhaled breath

Early-stage disease and cancer diagnosis are of particular importance for effective patient identification as well as their treatment. Breath analysis is a promising method for this purpose which can help to detect disease biomarkers. Benzaldehyde and Indole gas molecules as members of volatile organic compounds (VOCs) are composed of a proportion of the exhaled breath and changes in the level of them from breath can be considered for colorectal cancer biomarkers. Due to these incentives, we scrutinized the sensing behavior of Molybdenum disulfide (MoS[Formula: see text] toward Benzaldehyde and Indole gas. We inspected the adsorption of the molecules on the pristine and Pd-, Pt-decorated MoS2 by employing density functional nonequilibrium Green’s function (DFT-NEGF). It was disclosed that the molecules were weakly adsorbed upon the pristine MoS2. Howbeit, after the decoration of the surface, the adsorption energy and charge transfer of the molecules were improved greatly. On the other hand, the band gap was decreased after metal decoration. For example, adsorption energy of −2.37[Formula: see text]eV and band gap of 1.32[Formula: see text]eV were achieved by interaction of Indole with Pd-decorated MoS2 and it can be desorbed under UV light and at temperature of 698[Formula: see text]K with recovery time of 12.8[Formula: see text]s. Ergo, our analysis would help us better understand the adsorption mechanism of Pd- and Pt-decorated MoS2-based gas sensors. It may open a new route in early disease detection and colorectal cancer monitoring.

Thermosensitive visible-light-excited visible-/NIR-luminescent complexes with lanthanide sensitized by the π-electronic system through intramolecular H-bonding.

Visible-luminescent lanthanide (LnL) complexes with a highly planar tetradentate ligand were successfully developed for a visible-light solid-state excitation system. L was designed by using two 2-hydroxy-3-(2-pyridinyl)-benzaldehyde molecules bridged by ethylenediamine, which was then coordinated to a series of Ln ions (Ln = Nd, Sm, Eu, Gd, Tb, Dy, and Yb). From the measurement of single-crystal X-ray analysis of EuL, two phenolic O atoms and two imine N atoms in L were coordinated to the Eu ion, and each π-electronic system took coplanar with the edged-pyridine moiety through an intramolecular hydrogen bond. The enol group on the phenolic skeleton changed to the keto form, and the pyridine was protonated. Thus, intramolecular proton transfer occurred in L after the complexation. Other complexes take isostructure. The space group is P-1, and the c-axis shrinks with decreasing temperature without a phase transition in EuL. The yellow color caused by the planar structure of L can sensitize ff emission by visible light, and the luminescence color of each complex depends on central Ln ions. Furthermore, a phosphorescence band also appeared at rt with ff emission in LnL. Drastic temperature dependence of luminescence was clarified quantitatively.

Co0.6Ni0.4S2/rGO Photocatalyst for One-Pot Synthesis of Imines from Nitroaromatics and Aromatic Alcohols by Transfer Hydrogenation

Co0.6Ni0.4S2/rGO catalysts exhibit excellent photocatalytic performance for one-step synthesis of N-benzylideneaniline from nitrobenzene and benzyl alcohol by transfer hydrogenation, and the selectivity and yield of N-benzylideneaniline can reach as high as 93% and 77.2%, respectively. The reaction process for the synthesis of imines can be divided into two steps: benzyl alcohol is oxidized to benzaldehyde, while nitrobenzene is reduced to aniline; benzaldehyde and aniline are condensed to form imines. Under visible light irradiation, photo-induced electrons in Co0.6Ni0.4S2/rGO photocatalyst play an important role in activating nitrobenzene and benzaldehyde. Photo-induced holes are mainly responsible for the partial dehydrogenation of benzyl alcohol to benzaldehyde. Next, aniline molecules condense with benzaldehyde molecules to synthesize imine. The photocatalytic system provides an environmentally friendly for the synthesis of imines and supplies an alternative approach for hydrogen auto-transfer reactions.

Boroxine benzaldehyde complex for pharmaceutical applications probed by electron interactions.

2,4,6-Tris(4-formylphenyl)boroxine (TFPB) is a substituted boroxine containing a benzaldehyde molecule bonded to each boron atom. Boroxine cages are an emerging class of functional nanostructures used in host-guest chemistry, and benzaldehyde is a potential radiosensitizer. Reactions initiated by low-energy electrons with such complexes may dictate and bring new fundamental knowledge for biomedical and pharmaceutical applications. The electron ionization properties of TFPB are investigated using a gas-phase electron-molecule crossed beam apparatus coupled with a reflectron time-of-flight mass spectrometer in an orthogonal geometry. Ionization and threshold energies are experimentally determined by mass spectra acquisition as a function of the electron energy. The abundance of the molecular precursor cation in the mass spectrum at 70 eV is significantly lower than that of the most abundant fragment C7 H5 O+ . Twenty-nine cationic fragments with relative intensities >2% are detected and identified. The appearance energies of six fragment cations are reported, and the experimental first ionization potential is found at eV. Moreover, eight double cations are identified. The present results are supported by quantum chemical calculations based on bound state techniques, electron ionization models and thermodynamic thresholds. According to these results, the TPFB properties may combine the potential radiosensitizer effect of benzaldehyde with the stability of the boroxine ring.

Crystallographic Characterisation of Organolithium and Organomagnesium Intermediates in Reactions of Aldehydes and Ketones

AbstractWe report reactions of LiNacNac and NacNacMg(TMP) with common organic substrates (TMP=2,2,6,6‐tetramethylpiperidide). Using bulky β‐diketiminate compound NacNac (Me, Dipp), we have trapped metalated intermediates amenable to X‐ray crystallographic study. LiNacNac and acetone produced the NacNac‐free hexameric diacetone alkoxide [{LiO(MeC(=O)CH2C(Me)2}6]; whereas pinacolone gave the simple monomeric donor–acceptor complex [Li{(MeCN‐2,6‐iPr2C6H3)2CH}{O=C(Me)tBu}]. Benzaldehyde produced dimeric [Li{(MeCN‐2,6‐iPr2C6H3)2CC(=O)Ph}{O=C(Ph)OCH2Ph}]2, where one benzaldehyde molecule has inserted in to the γ‐carbon position of the NacNac ligand, with a molecule of benzyl benzoate derived from a Tishchenko reaction of the aldehyde acting as a terminal donor to lithium. Tetranuclear, mixed dimer [{LiO(MeCN‐2,6‐iPr2C6H3)2CH‐CH(Ph)}2{LiO(PhC(=O)}2] containing the same modified NacNac ligand was the fortuitous product from repeating the reaction of LiNacNac and benzaldehyde in a solution presumably contaminated with benzoic acid. Combining NacNacMg(TMP) with pinacolone affords monomeric heteroleptic [Mg{(MeCN‐2,6‐iPr2C6H3)2CH}{OC(tBu)(Me)CH2C(=O)tBu}] with an aldolate constituting the second anion. Completing the set is dimeric [Mg{(MeCN‐2,6‐iPr2C6H3)2CH}{O(C=CH2)Ph}2], where the enolate derived from acetophenone bridges the magnesium centres.

Porous Mn-doped Co3O4 nanosheets: Gas sensing performance and interfacial mechanism investigation with In situ DRIFTS

Unraveling the gas-solid interfacial sensing mechanism during gas sensing is very essential for the development of high-performance gas sensors. In this work, the Mn-doped Co3O4 porous nanosheets with 5.6 times higher response than pristine Co3O4 and short response/recovery time (55/30 s) for 100 ppm toluene gas is synthesized. More importantly, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) is conducted to investigate the gas-solid interfacial sensing mechanism over 3-Mn-Co3O4. The interfacial reaction species have been monitored, such as methylbenzene, benzyl alcohol, benzaldehyde, benzoic acid, carbon monoxide, and water molecule. These species originate from the elementary and overall reactions during toluene gas sensing. The dynamic evolution of surface species could be divided into three stages of adsorption reaction, reaction balance, and desorption reaction. Furthermore, combined with the density function theory simulation calculation, the gas-solid interfacial sensing mechanism over 3-Mn-Co3O4 is proposed. Toluene molecule reacts with the surface active oxygen species resulting in the occurrence of a series of elementary reactions and the generation of intermediates. The products of overall reaction are CO2 and H2O during gas sensing. Our work implements a meaningful exploration of in situ DRIFTS in gas-sensing field and provides a distinctive view to understand the gas-soild interfacial gas-sensing mechanism.

Aldol Reactions of Conformationally Stable Axially Chiral Thiohydantoin Derivatives.

Two novel axially chiral ortho-trifluoromethylphenyl thiohydantoin derivatives have been prepared atroposelectively from the reaction of R and S alanine methyl ester HCl salts with ortho-trifluoromethylphenyl isothiocyanate in the presence of triethyl amine. It was found that after purification of the crude product by simple recrystallization, the R amino acid esters yielded thiohydantoins having solely M axial chirality whereas the S ones returned the P isomers only. This result prompted us to perform sterically controlled aldol reactions on M and P thiohydantoin atropisomers. It was found that during the aldol reaction of 3-o-trifluoromethyl-5-methylthiohydantoins, the o-trifluoromethyl group of the M isomers efficiently shielded the Si face of the intermediate and in this way, enabled the selective formation of only the R configured aldol products at C5 of the heterocyclic ring. The P thiohydantoins, on the other hand, yielded only the S C5 configured aldol products as a result of the Re face shielding of the ortho-trifluoromethyl group of intermediate enolates. A noteworthy face selectivity of the benzaldehyde molecule was not observed (anti/syn only 3/2) during the aldolization of trifluoromethylphenyl derivatives of thiohydantoins. Aldol reactions were also done using the previously synthesized axially chiral thiohydantoins with ortho-Cl, Br, and I phenyl substituents which had predominantly P conformations (P/M ratios > 95%), and the stereochemical outcomes were compared with those of the ortho-trifluoromethyl substituted ones. 80–90% face selectivity of the benzaldehyde molecule was observed for the axially chiral o-halophenyl substituted thiohydantoins. The syntheses done with axially chiral 3-ortho-trifluoromethylphenyl- and 3-ortho-iodophenyl-5-methyl thiohydantoins enabled stereoselective formation of quaternized chiral carbon centers at C5 of the thiohydantoin ring.

Fine-tuning directionality of ESIPT behavior of the asymmetric two proton acceptor system via atomic electronegativity

The excited state intramolecular proton transfer (ESIPT) processes and photophysical features of 3-(benzo[d]oxazol-2-yl)-2-hydroxy-5-methoxy benzaldehyde (BOHMB) and 3-(benzo[d]selenazole-2-yl)-2-hydroxy-5-methoxy benzaldehyde (BSeHMB) molecules were investigated in detail by using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. The strengthened excited state hydrogen bonds (H-bond) of the title compounds are favorable to ESIPT process according to the analyses of structural parameter, infrared vibration frequency, electron density and reduced density gradient. The atomic substitution changes the intramolecular H-bond O1-H2…O3 and O1-H2…N4 and the fluorescence emission peaks of BOHMB-N and BSeHMB-N in normal and tautomer forms. The potential energy curves indicate that the ESIPT energy barriers of BOHMB-O, BTHMB-O and BSeHMB-O increase as the electron-withdrawing abilities of atoms (from O to S and Se) are gradually weakened. However, the ESIPT energy barriers of BOHMB-N and BTHMB-N follow the totally opposite order. For BOHMB and BSeHMB, ESIPT process prefers to occur in the direction from O-H group to the O atom.

Identification and Detection of Volatile Aldehydes as Lung Cancer Biomarkers by Vapor Generation Combined with Paper-Based Thin-Film Microextraction.

Accurate, sensitive, and selective on-spot screening of volatile aldehydes as lung cancer biomarkers is of vital significance for preclinical diagnosis and treatment guidance of cancers. However, the common methods of sensing biomarkers are limited by the fact that they are time-consuming, require professional personnel, and have complex matrixes. Here, we developed a smart vapor generation paper-based thin-film microextraction system capable of both sensitive on-field fluorescence detection and accurate surface-enhanced Raman spectroscopy (SERS) quantification of volatile benzaldehyde (BA) by utilizing stimuli-responsive core-shell gold nanorod (GNR) quantum dot (QD)-embedded metal-organic framework (MOF) structures. The amino-modified GNRs and carboxyl-capped QDs can directly assemble with each other by electrostatic interaction, which leads to an almost complete emission quenching of QDs. The addition of BA molecules destroys the GNRs-QD assemblies due to the Schiff base reactions between the amine group of 4-mercaptonoaniline and the aldehyde moiety of BA, resulting in the increase of the fluorescence and Raman signal of hybrid systems, which enables the visualization of BA with the naked eye. Moreover, the "cavity-diffusion" effect of porous MOF shells validates the selective concentration of gaseous BA molecules on the GNR surface, allowing the discrimination of BA in exhaled breath rapidly and precisely even at the sub-ppb level with excellent specificity against other volatile organic compounds. This study not only offers a versatile sensing platform for accurate discrimination of lung cancer from controls but also opens an avenue for the design of smart sensors for point-of-care applications.

Metal-free porous phosphorus-doped g-C3N4 photocatalyst achieving efficient synthesis of benzoin.

Photocatalytic organic synthesis is mostly limited by the shortcomings of insufficient light absorption, high photogenerated electron–hole recombination rate and inadequate reactive sites of photocatalysts. To solve these problems, phosphorus-doped g-C3N4 with a porous structure was constructed. Benefiting from enhanced light absorption and electron–hole separation efficiency, PCNT has intensive oxygen activation ability to generate superoxide radicals, and is highly active in organic synthesis. In addition, PCNT has enhanced surface nucleophilicity, which is conducive to the carbon–carbon coupling process of the intermediate product benzaldehyde molecules and benzyl alcohol molecules in the benzoin condensation reaction. Metal-free PCNT is expected to replace the previously used highly toxic cyanide catalysts and provide a new way for the low-cost and efficient photocatalytic synthesis of benzoin.

Revised the excited-state intramolecular proton transfer direction of the BTHMB molecule: A theoretical study

The spectroscopic properties of 3-(benzo[d]-thiazol-2-yl)-2-hydroxy-5-methoxy benzaldehyde molecule were investigated [J. Phys. Chem. A 2019, 123, 10246–10253]. The result shows that the excited-state intramolecular proton transfer (ESIPT) was driven toward the N center over the O center. In this research, the density functional theory and time-dependent density functional theory method were used to calculate molecule structures. Through our calculations, the ESIPT process toward N atom is proved to be feasible. Moreover, the emission peak we obtained of ESIPT process from the OH proton to aldehyde O atom is located at 564 nm, which is attributed to 500 nm in previous research. From the potential energy curves, the 0.35 kcal/mol energy barrier indicates the ESIPT process could occur when excited to S1 state from the OH proton to aldehyde O atom. In addition, the frontier molecular orbitals analysis and IR spectrum were also calculated. Finally, we revise the direction of BTHMB molecule, the two directions of ESIPT are both feasible when excited to S1 state.

Solvent-Free Synthesis of Jasminaldehyde in a Fixed-Bed Flow Reactor over Mg-Al Mixed Oxide

In spite of the rapid developments in synthesis methodologies in different fields, the traditional methods are still used for the synthesis of organic compounds, and regardless of the type of chemistry, these reactions are typically performed in standardized glassware. The high-throughput chemical synthesis of organic compounds such as fragrant molecules, with more economic benefits, is of interest to investigate and develop a process that is more economical and industrially favorable. In this research, the catalytic activity of Mg-Al catalyst derived from hydrotalcite-like precursors with the Mg/Al molar ratio of 3 was investigated for the solvent-free synthesis of jasminaldehyde via aldol condensation of benzaldehyde and heptanal. The reaction was carried out in a fixed-bed flow reactor, at 1 MPa, and at different temperatures. Both Brønsted and Lewis (O2− anions) base sites, and Lewis acid sites exist on the surface of the Mg-Al catalyst, which can improve the catalytic performance. Increasing the reaction temperature from 100 °C to 140 °C enhanced both heptanal conversion and selectivity to jasminaldehyde. After 78 h of reaction at 140 °C, the selectivity to jasminaldehyde reached 41% at the heptanal conversion 36%. Self-condensation of heptanal also resulted in the formation of 2-n-pentyl-2-n-nonenal. The presence of weak Lewis acid sites creates a positive charge on the carbonyl group of benzaldehyde, and makes it more prone to attack by the carbanion of heptanal. Heptanal, is an aliphatic aldehyde, with higher activity than benzaldehyde. Therefore, the possibility of activated heptanal reacting with other heptanal molecules is higher than its reaction with the positively charged benzaldehyde molecule, especially at a low molar ratio of benzaldehyde to heptanal.

Revealing aggregation-induced emission effect of imidazolium derivatives and application for detection of Hg2+

Despite being highly emissive in solution, aggregation of 4-(4,5-bis(4-methoxyphenyl)-1H- imidazole-2-yl) benzaldehyde (BMI) molecules typically results in the quenching of fluorescence. To overcome the shortcomings of aggregation-caused quenching (ACQ), the substituent of imidazole in the nitrogen atom of the BMI have been found as a conformation function group (CFG) to turn the aggregation-induced emission (AIE) effect. The introduction of CFG not only causes the restriction of intramolecular rotations (RIR) effect, but also attenuates the coplanarity of the molecule. As a result, the BMI with ACQ effect is transformed into BMIs with AIE effect. As the steric hindrance of the CFG increases, the AIE characteristic of the derivative also becomes apparent. With the assistance of the thioacetal unit, BMIBD can act as an outstanding probe for the detection of Hg2+ with high sensitivity and selectivity. A series of characterizations were implemented to prove the unique response mechanism of BMIBD toward mercury ions, including optical behavior investigation, mass analysis and 1H NMR studies. Further, the detection limit is low up to 36 nM. Taking advantages of excellent optical properties of this AIE probe BMIBD, point-of-care testing (POCT) for Hg2+ detection was further investigated. Meanwhile, BMIBD presented the desirable analytical property for the real water samples. Additionally, cellular imaging experiment revealed that the probe has an excellent biocompatibility that could be applied for tracking Hg2+ in living cells.

Real-Time Propagation TDDFT and Density Analysis for Exciton Coupling Calculations in Large Systems.

Photoactive systems are characterized by their capacity to absorb the energy of light and transform it. Usually, more than one chromophore is involved in the light absorption and excitation transport processes in complex systems. Linear-Response Time-Dependent Density Functional (LR-TDDFT) is commonly used to identify excitation energies and transition properties by solving the well-known Casida’s equation for single molecules. However, in practice, LR-TDDFT presents some disadvantages when dealing with multichromophore systems due to the increasing size of the electron–hole pairwise basis required for accurate evaluation of the absorption spectrum. In this work, we extend our local density decomposition method that enables us to disentangle individual contributions into the absorption spectrum to computation of exciton dynamic properties, such as exciton coupling parameters. We derive an analytical expression for the transition density from Real-Time Propagation TDDFT (P-TDDFT) based on Linear Response theorems. We demonstrate the validity of our method to determine transition dipole moments, transition densities, and exciton coupling for systems of increasing complexity. We start from the isolated benzaldehyde molecule, perform a distance analysis for π-stacked dimers, and finally map the exciton coupling for a 14 benzaldehyde cluster.