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The dynamics of molecular excitonic systems are complicated by a competition between electronic coupling (which drives delocalization) and vibrational-electronic (vibronic) interactions (which tend to encourage electronic localization). A particular challenge of molecular systems is that they typically possess a large number of independent vibrations, with frequencies often spanning the entire spectrum of relevant electronic energy gaps. Recent spectroscopic observations and numerical simulations on a water-soluble chlorophyll-binding protein (WSCP) reveal a transition between two regimes of vibronic behavior, a Redfield-like regime in which low-frequency vibrations respond to a delocalized excitonic state, and a Förster-like regime where high-frequency vibrations act as incoherent excitations on individual pigments. Although numerical simulations can reproduce these effects, there is a need for a simple, systematic theory that accurately describes the smooth transition between these two regimes in experimental spectra. Here we address this challenge by generalizing the variational polaron transform approach of [Bloemsma et al., Chem. Phys. 481, 250 (2016)] to include arbitrary bath densities for systems with or without symmetry. We benchmark this theory against both numerical matrix-diagonalization methods and experimental 77 K fluorescence spectra for two WSCP variants, obtaining quite satisfactory agreement in both cases. We apply this theory to offer an explanation for the large loss in apparent electronic coupling in the WSCP Q57K mutant and to examine the likely impact of the interplay between excitonic delocalization and vibrational localization on vibrational sideband shapes and apparent coupling strengths in high-resolution optical spectra for chlorophyll-protein complexes such as WSCP. [ABSTRACT FROM AUTHOR]

Accurately predicting spectra for heavy elements, often open-shell systems, is a significant challenge typically addressed using a single cluster approach with a fixed coordination number. Developing a realistic model that accounts for temperature effects, variable coordination numbers, and interprets experimental data is even more demanding due to the strong solute–solvent interactions present in solutions of heavy metal cations. This study addresses these challenges by combining multiple methodologies to accurately predict realistic spectra for highly charged metal cations in aqueous media, with a focus on the electronic absorption spectrum of Ce3+ in water. Utilizing highly correlated relativistic quantum mechanical (QM) wavefunctions and structures from molecular dynamics (MD) simulations, we show that the convolution of individual vertical transitions yields excellent agreement with experimental results without the introduction of empirical broadening. Good results are obtained for both the normalized spectrum and that of absolute intensity. The study incorporates a statistical machine learning algorithm, Gaussian Mixture Models-Nuclear Ensemble Approach (GMM-NEA), to convolute individual spectra. The microscopic distribution provided by MD simulations allows us to examine the contributions of the octa- and ennea-hydrate of Ce3+ in water to the final spectrum. In addition, the temperature dependence of the spectrum is theoretically captured by observing the changing population of these hydrate forms with temperature. We also explore an alternative method for obtaining statistically representative structures in a less demanding manner than MD simulations, derived from QM Wigner distributions. The combination of Wigner-sampling and GMM-NEA broadening shows promise for wide application in spectroscopic analysis and predictions, offering a computationally efficient alternative to traditional methods. [ABSTRACT FROM AUTHOR]

In this work, we explore the electronic properties and chemical bonding in the recently discovered mineral zaykovite, the first natural rhodium selenide Rh3Se4. We comprehensively studied the bulk electronic structure, hybridization of rhodium and selenium orbitals, and the influence of spin–orbit interaction on the electronic spectrum, as well as inspected its topological properties. In addition, we investigated the surface electronic structure of zaykovite and revealed the anisotropic Rashba-type spin splitting in the surface states. In addition, using calculations of the phonon spectra and enthalpy of formation, we predicted the family of similar selenides based on other 4d and 5d transition metals such as Ir, Pd, and Pt. The structural and electronic properties of these materials are discussed. [ABSTRACT FROM AUTHOR]

In this work, we explore the electronic properties and chemical bonding in the recently discovered mineral zaykovite, the first natural rhodium selenide Rh3Se4. We comprehensively studied the bulk electronic structure, hybridization of rhodium and selenium orbitals, and the influence of spin–orbit interaction on the electronic spectrum, as well as inspected its topological properties. In addition, we investigated the surface electronic structure of zaykovite and revealed the anisotropic Rashba-type spin splitting in the surface states. In addition, using calculations of the phonon spectra and enthalpy of formation, we predicted the family of similar selenides based on other 4d and 5d transition metals such as Ir, Pd, and Pt. The structural and electronic properties of these materials are discussed. [ABSTRACT FROM AUTHOR]

For the computation of vibrationally resolved electronic spectra, various approaches can be employed. Adiabatic approaches simulate vibronic transitions using harmonic potentials of the initial and final states, while vertical approaches extrapolate the final state potential from the gradients and Hessian at the Franck–Condon point, avoiding a full exploration of the potential energy surface of the final state. Our implementation of the vertical Hessian (VH) method has been validated with a benchmark set of four small molecules, each presenting unique challenges, such as complex topologies, problematic low-frequency vibrations, or significant geometrical changes upon electronic excitation. We assess the quality of both adiabatic and vertical approaches for simulating vibronic transitions. For two types of donor–acceptor compounds with promising thermally activated delayed fluorescence properties, our computations confirm that the vertical approaches outperform the adiabatic ones. The VH method significantly reduces computational costs and yields meaningful emission spectra, where adiabatic models fail. More importantly, we pioneer the use of the VH method for the computation of rate constants for non-radiative processes, such as intersystem crossing and reverse intersystem crossing along a relaxed interpolated pathway of a donor–acceptor compound. This study highlights the potential of the VH method to advance computational vibronic spectroscopy by providing meaningful simulations of intricate decay pathway mechanisms in complex molecular systems. [ABSTRACT FROM AUTHOR]

This work presents a theoretical analysis of the oscillations of a system of degenerate electrons in metallic submicron clusters, taking into account the presence of a large-scale spatial inhomogeneity caused by quantum shell effects. The analysis was carried out in a model formulation in which the large-scale effect was taken into account by the presence of an effective external field acting on the electrons. Two approaches to the description of electron dynamics were considered: kinetic and hydrodynamic. The results obtained within these approaches are in good qualitative and quantitative agreement with each other and demonstrate that for certain cluster sizes, a spectrum of oscillations of the electronic system appears with frequencies differing by the value Δω ∼ ω0/R20 and localized in the vicinity of plasmon frequency ω0 (R0, radius of cluster). The impact of the large-scale effect on the processes of light and electron scattering by metal clusters is estimated. It is shown that maxima appear in the absorption spectrum of the electromagnetic waves, and they turn out to be shifted from the plasmon frequency by value Δω ∼ ω0/R20. Within the framework of the Born approximation, it is shown that a maximum at kR0 ∼ 4π appears in the cross section of elastic scattering of electrons on a metal cluster. The results obtained are important from the point of view of interpreting experiments on plasmonic structures, in particular, on metal films. [ABSTRACT FROM AUTHOR]

This study was focused on the photochemistry of OAlOH and three possible pathways, which were studied with high-level multireference configuration interaction ab initio calculations. We computed cuts of the six-dimensional potential energy surfaces for the ground, the lowest singlet and triplet excited states, and probed the photodissociation mechanisms and the stabilities. The OAlOH electronic spectrum, with an energy reaching 7.15 eV, contained four prominent peaks. Photodissociation to AlO, OH, and AlOH constituted a plausible mechanism within the deep-UV range (λ = 250.4 nm). Our data indicated the photostability of OAlOH in the near-UV‒Vis region, so detection with laser-induced fluorescence is possible. Fluorescence and phosphorescence may occur upon excitation at 363.5 nm. The roles of OAlOH in the photochemical reactions of Al-bearing molecules in the upper atmosphere and VY Canis Majoris are discussed. [ABSTRACT FROM AUTHOR]

We investigate how electronic excitations and subsequent dissipative dynamics in the water soluble chlorophyll-binding protein (WSCP) are connected to features in two-dimensional (2D) electronic spectra, thereby comparing results from our theoretical approach with experimental data from the literature. Our calculations rely on third-order response functions, which we derived from a second-order cumulant expansion of the dissipative dynamics involving the partial ordering prescription, assuming a fast vibrational relaxation in the potential energy surfaces of excitons. Depending on whether the WSCP complex containing a tetrameric arrangement of pigments composed of two dimers with weak excitonic coupling between them binds the chlorophyll variant Chl a or Chl b, the resulting linear absorption and circular dichroism spectra and particularly the 2D spectra exhibit substantial differences in line shapes. These differences between Chl a WSCP and Chl b WSCP cannot be explained by the slightly modified excitonic couplings within the two variants. In the case of Chl a WSCP, the assumption of equivalent dimer subunits facilitates a reproduction of substantial features from the experiment by the calculations. In contrast, for Chl b WSCP, we have to assume that the sample, in addition to Chl b dimers, contains a small but distinct fraction of chemically modified Chl b pigments. The existence of such Chl b derivates has been proposed by Pieper et al. [J. Phys. Chem. B 115, 4042 (2011)] based on low-temperature absorption and hole-burning spectroscopy. Here, we provide independent evidence. [ABSTRACT FROM AUTHOR]

Identifying the oxidation structure of two-dimensional interfaces is crucial to improve surface chemistry and electronic properties. Beyond graphene with only phenyl rings, a novel carbon-nitrogen material, C3N, presents an intrinsic heterogeneous surface morphology where each phenyl ring is encircled by six nitrogen atoms, yet its atomistic oxidation structure remains unclear. Here, combining a series of density functional theory calculations and ab initio molecular dynamics simulations, we demonstrate that thermodynamically favorable oxidation loci are confined to the phenyl ring, and kinetic transformations of oxidation structures are feasible along the phenyl ring, whereas those toward nitrogen atoms are proven to be extremely difficult. These results are attributed to the lower barrier of oxygen atom migration along the phenyl ring, while the significantly high barriers toward nitrogen atoms are due to the heterogeneous potential energy surface for oxygen–C3N interaction. This work highlights the significance of surface morphology on the characteristics of oxidation structure, offering insights into tunable electronic properties via confined interfacial oxidation. [ABSTRACT FROM AUTHOR]

Wave packet interferometry with vacuum ultraviolet light has been used to probe a complex region of the electronic spectrum of molecular nitrogen, N2. Wave packets of Rydberg and valence states were excited by using double pulses of vacuum ultraviolet (VUV), free-electron-laser (FEL) light. These wave packets were composed of contributions from multiple electronic states with a moderate principal quantum number (n ∼ 4–9) and a range of vibrational and rotational quantum numbers. The phase relationship of the two FEL pulses varied in time, but as demonstrated previously, a shot-by-shot analysis allows the spectra to be sorted according to the phase between the two pulses. The wave packets were probed by angle-resolved photoionization using an infrared pulse with a variable delay after the pair of excitation pulses. The photoelectron branching fractions and angular distributions display oscillations that depend on both the time delays and the relative phases of the VUV pulses. The combination of frequency, time delay, and phase selection provides significant control over the ionization process and ultimately improves the ability to analyze and assign complex molecular spectra. [ABSTRACT FROM AUTHOR]

We present a numerically exact approach for evaluating vibrationally resolved electronic spectra at finite temperatures using the coherence thermofield dynamics. In this method, which avoids implementing an algorithm for solving the von Neumann equation for coherence, the thermal vibrational ensemble is first mapped to a pure-state wavepacket in an augmented space, and this wavepacket is then propagated by solving the standard, zero-temperature Schrödinger equation with the split-operator Fourier method. We show that the finite-temperature spectra obtained with the coherence thermofield dynamics in a Morse potential agree exactly with those computed by Boltzmann-averaging the spectra of individual vibrational levels. Because the split-operator thermofield dynamics on a full tensor-product grid is restricted to low-dimensional systems, we briefly discuss how the accessible dimensionality can be increased by various techniques developed for the zero-temperature split-operator Fourier method. [ABSTRACT FROM AUTHOR]

We present a detailed theoretical analysis of polarized absorption spectra and linear dichroism of cyanine dye aggregates whose unit cells contain two molecules. The studied threadlike ordered system with a molecular exciton delocalized along its axis can be treated as two chains of conventional molecular aggregates, rotated relative to each other at a certain angle around the aggregate axis. Our approach is based on the general formulas for the effective cross section of light absorption by a molecular aggregate and key points of the molecular exciton theory. We have developed a self-consistent theory for describing the orientational effects in the absorption and dichroic spectra of such supramolecular structures with nonplanar unit cell. It is shown that the spectral behavior of such systems exhibits considerable distinctions from that of conventional cyanine dye aggregates. They consist in the strong dependence of the relative intensities of the J- and H-type spectral bands of the aggregate with a nonplanar unit cell on the angles determining the mutual orientations of the transition dipole moments of constituting molecules and the aggregate axis as well as on the polarization direction of incident light. The derived formulas are reduced to the well-known analytical expressions in the particular case of aggregates with one molecule in the unit cell. The calculations performed within the framework of our excitonic theory combined with available vibronic theory allow us to quite reasonably explain the experimental data for the pseudoisocyanine bromide dye aggregate. [ABSTRACT FROM AUTHOR]

Doubly resonant sum frequency generation (DR-SFG) serves as a potent characteristic technique for probing the electronic spectra and vibronic coupling of molecules on surfaces. In this study, we successfully developed a novel infrared (IR)–white light (WL) DR-SFG spectroscopy based on narrowband IR and tunable broadband WL. This novel method was employed to explore the excitation spectrum and vibronic couplings of sub-monolayer Rhodamine 6G molecules. Our findings elucidate that the xanthene skeleton vibrational modes exhibit strong coupling with the S0–S1 electronic transition. Notably, we observed not only the 0–0 transition of the S0–S1 electronic continuum but also the 0–1 transition, a first time observation in the realm of DR-SFG spectroscopy. This advanced DR-SFG spectroscopy methodology facilitates a more sensitive examination of electronic spectra and the coupling between electronic transitions and vibrational modes, heralding a significant advancement in the understanding of molecular interactions on surfaces. [ABSTRACT FROM AUTHOR]

To spectroscopically qualify strength in the π-electron conjugation, the electronic spectra of jet-cooled 1,4-bis(phenylethynyl)benzene (BPEB) in the region of the transition to the lowest excited singlet (S1) 1B1u state are measured by the fluorescence excitation and the single-vibronic-level dispersed fluorescence methods. Strength is defined as the difference in potential energies between the planar and perpendicular conformations. BPEB possesses two large-amplitude torsional motions, out-of-phase 24 and in-phase 29 modes. The most stable is the planar conformation, and barrier heights at the perpendicular conformation are coincident in torsional potentials for the two modes. Torsional levels are successively observed up to 19± and 16− quantum levels in the ground state, respectively. Strength is determined to be 293 cm−1 (3.51 kJmol−1) with an accuracy of an error range smaller than 1 cm−1. In the excited state, strength is estimated to be 1549 ± 73 cm−1. Combination levels of two torsional modes are also measured up to high quantum levels. A systematic decrease in frequencies is observed with increasing the quantum number. Quantum-chemistry calculations of B3LYP, CAM-B3PLYP, WB97XD, and M062X with basis sets of aug-cc-pVDZ are performed, where B3LYP theories are carried out with the dispersion correlation. The calculated strength is 1.1–2.1 times larger than observed. [ABSTRACT FROM AUTHOR]

Ultraviolet and vacuum ultraviolet photo-absorption spectra of azido (–N3)-based energetic plasticizer, bis(1,3-diazido-prop-2-yl)-malonate (abbreviated as BDAzPM), in the gas phase is recorded at room temperature and in the photon energy range of 5.5–9.9 eV using a synchrotron radiation source. Complementary computational results obtained using the time-dependent density functional theory document the vertical transition energies and oscillator strengths. Comparison of the simulated spectra with the experimental absorption spectrum of BDAzPM reveals that the early part of the absorption spectrum of BDAzPM is of pure valence excitation character, whereas the later intense part of the absorption spectrum is dominated by mixed Rydberg and valence electronic excitations. [ABSTRACT FROM AUTHOR]

Time-resolved pump–probe and two-dimensional spectroscopy are widely used to study ultrafast chemical and biological processes in solutions. However, the corresponding signals at long times can be contaminated by molecular photothermal effects, which are caused by the nonradiative heat dissipation of photoexcited molecules to the surroundings. Additionally, molecular diffusion affects the transient spectroscopic signals because photoexcited molecules can diffuse away from the pump and probe beam focuses. Recently, a theoretical description of molecular photothermal effects on time-resolved IR spectroscopy was reported. In this work, I consider the molecular photothermal process, molecular diffusion, and sample flow to develop a generalized theoretical description of time-resolved spectroscopy. The present work can be used to interpret time-resolved spectroscopic signals of electronic or vibrational chromophores and understand the rate and mechanisms of the conversion of high-frequency molecular electronic and vibrational energy to solvent kinetic energy in condensed phases. [ABSTRACT FROM AUTHOR]

Nonlinear optical methods, such as vibrational sum frequency generation (vSFG) and second harmonic generation (SHG), are powerful techniques to study elusive structures at charged buried interfaces. However, for the separation and determination of the Stern and diffuse layer spectra at these charged interfaces, complex vSFG spectra and, hence, the absolute phase need to be retrieved. The maximum entropy method is a useful tool for the retrieval of complex spectra from the intensity spectra; however, one caveat is that an understanding of the error phase is required. Here, for the first time, we provide a physically motivated understanding of the error phase. Determining the error phase from simulated spectra of oscillators with a spectral overlap, we show that for broadband vSFG spectra, such as for the silica/water interface, the diffuse and Stern layers' spectral overlap within the O–H stretching window results in a correlation between the error phase and the phase shift between the responses of these layers. This correlation makes the error phase sensitive to changes in Debye length from varying the ionic strength among other variations at the interface. Furthermore, the change in the magnitude of the error phase can be related to the absolute SHG phase, permitting the use of an error phase model that can utilize the SHG phase to predict the error phase and, hence, the complex vSFG spectra. Finally, we highlight limitations of this model for vSFG spectra with a poor overlap between the diffuse and Stern layer spectra (silica/HOD in D2O system). [ABSTRACT FROM AUTHOR]

A theory is presented for the amplification of a surface acoustic wave (SAW) due to its interaction with conduction electrons in gate-controlled epitaxial graphene (epigraphene) on a SiC substrate. It is assumed that the SAW is launched onto the substrate in the direction of an external dc electric field applied to the graphene sample and causing the conduction electrons to drift at a speed greater than the speed of the SAW. The wavelength of the SAW is assumed to be shorter than the mean free path of the electrons, so that the quantum regime of interaction of those electrons with the SAW is realized. The Green's function method is used to calculate the SAW gain as a function of the electron concentration in epigraphene and the external dc electric field strength. It is shown that the substrate-induced band gap in the electronic spectrum of epigraphene leads to a significant (at least an order of magnitude) increase in the SAW gain as compared to the case of gapless graphene. In addition, the opening of the band gap results in a non-monotonic dependence of the SAW gain on the electron concentration, controlled by the gate voltage applied to the graphene sample. This dependence is characterized by the presence of a distinct maximum at a certain value of electron concentration (of about 2 × 10 12 cm−2 for typical values of the other parameters involved), which distinguishes it from the monotonic concentration dependence of the SAW gain in gapless graphene. [ABSTRACT FROM AUTHOR]

Investigations into topological materials typically emphasize either electronic or phononic properties in isolation, often disregarding their coexistence, which could restrict the full realization of their practical applications. Here, we investigate HOD-graphene, an emergent macroporous carbon material featuring a unique configuration of hexagonal, octagonal, and dodecagonal carbon rings. This distinctive structure imparts exceptional mechanical properties to the material. Using a combination of first-principles calculations and symmetry analysis, we demonstrate that HOD-graphene hosts multiple nodal lines within both its electronic and phononic spectra. For the electronic bands, three nodal lines and several Dirac points manifest near the Fermi energy, generating unconventional electronic properties and distinct topological characteristics. Likewise, the phonon spectrum displays pronounced nodal lines, intricately associated with the material's vibrational modes. Our findings provide a promising platform for exploring the coexistence of electronic and phononic multiple nodal lines in two-dimensional materials, opening avenues for realizing exotic quantum phenomena. [ABSTRACT FROM AUTHOR]

Hexa(ethylhexyl)-hexa-(peri)-hexabenzocoronene (HEH-HBC) was selected as model compound of asphaltenes. In fact, in the "island" model the asphaltenes are described with a relatively large aromatic core surrounded by aliphatic chains attached to the edges of the core. In their turn the asphaltenes are considered model compounds of MAONs (Mixed Aromatic-aliphatic Organic Nanoparticles), the possible carriers of the Unidentified Infrared Bands (UIBs), i.e. a set of certain infrared features found in very different astrophysical objects. The differential scanning calorimetric analysis (DSC) shows that HEH-HBC displays a discotic liquid crystal behavior, similar to that observed also in a selected authentic petroleum asphaltene sample. The electronic absorption spectrum of HEH-HBC was recorded for the first time in hydrocarbon solvents fully transparent in the UV, permitting to observe the UV part of HEH-HBC and to compare it with that of unsubstituted HBC. The FT-IR spectrum of HEH-HBC was recorded not only at room temperature but also at higher resolution at the liquid nitrogen temperature. The molar extinction coefficients and integrated molar absorptivity of the main bands were also estimated. The results are briefly discussed from an astrochemical perspective. [ABSTRACT FROM AUTHOR]

A new novel NO pincer type bezo[d]thiazole ligand, 2‐(5,6‐dichlorobenzo[d]thiazol‐2‐yl)phenol (HDCBTP) is synthesized through reacting 2‐amino‐4,5‐dichlorobenzenethiol and 2‐hydroxybenzoic acid in 1:1 ratio. Nano‐sized bivalent Pt (II) complex is created and subsequently characterized using various physical methods. The complex structural geometry is validated by employing the density functional theory (DFT) approach, utilizing DMOL3 determinations. Based on the elemental analysis results, the complexes are inferred to follow the overall formula [Pt (DCBTP)2]. Quantum chemical calculations, along with electronic spectra findings, indicate that Pt (II) complex exhibits a square planar configuration. The XRD, EDX, TEM, and AFM analyses of the studied complex unveil distinct and strong diffraction peaks, indicating its crystalline nature and providing evidence of its nano‐sized particle sizes. Viscosity measurements and absorption titration techniques were used to study the interaction between Pt (II) complex and CT‐DNA. The results showed that the complexes were bound to CT‐DNA via a typical intercalation binding mode. The in vitro antimicrobial efficacy of HDCBTP and its Pt (II) complex was inspected against various bacterial and fungal pathogens. The results highlight these compounds as a highly effective fungicides and bactericides. In vitro cytotoxic effects of the formulated complex were explored utilizing PC3 prostate cancer cell lines. According to IC50 and selective index (SI) measurements, it was shown that the complex exhibited higher potency against HePG2 cell lines. Moreover, Pt (II) complex exhibited the capability for triggering DNA damage in HePG2 cells, resulting in dose‐dependent cell apoptosis. Subsequent investigations revealed that complex triggered cell cycle arrest during the S and G2 phases. [ABSTRACT FROM AUTHOR]

Infectious diseases, induced by various pathogenic microorganisms, can enter the body and disrupt normal physiological functions, leading to a range of symptoms and health complications. So, to ascertain a significant anti-infectious agent against antimalarial and anti-tuberculosis ailments, the previously synthesized and extensively characterized (mass spectrometry, NMR (1H and 13C), electronic spectra, infrared, magnetic moment, ESR, molar conductance, powder XRD, SEM and EDAX) Schiff base ligands (1–4) and their octahedral Co(II), Ni(II), Cu(II), Zn(II) complexes (5–20) were studied. The biological evaluation demonstrated that compounds (1, 5–8) and (3, 13–16) showed high potency against malaria and tuberculosis, respectively. Furthermore, Zn(II) complexes (8) and (16) exhibited the greatest efficacy, with IC50 value of 0.32 ± 0.06 µM and MIC value of 0.0081 µmol/mL. Moreover, molecular docking investigation against the 1U5A, 8E1Z proteins for malaria and 5V3Y, 3PTY proteins for TB, along with ADMET investigations, was conducted on highly active compounds (1, 3, 5–8, 13–16) to validate their biological findings. The theoretical analysis also supported the superior efficacy of (8) and (16) complexes, demonstrating their lowest binding affinity (1U5A (− 8.1 kcal/mol), 8E1Z (− 8.9 kcal/mol), 5V3Y (− 10.1 kcal/mol), 3PTY (− 10.2 kcal/mol)), favorable coordination modes and drug likeness property. [ABSTRACT FROM AUTHOR]

Near infrared (NIR) photodetectors (PDs) attain a great attention for their advanced optoelectornic applications such as high‐resolusion biomedical sensors. In particular, all‐polymer PDs composed of electron‐donating and electron‐accepting polymers in their active layer offer the advantage of various donor and acceptor combinations for easily tunable absorption spectra and electronic properties, along with superior mechanical durability and stability. In this study, two A1–π–A2‐type polymer acceptors are developed for efficient NIR light detection at 860 nm. The electron‐accepting diketopyrrolopyrrole (DPP) and dicyano‐substituted quinoxaline (Qx) units are linked through a dithiophene π‐bridge to generate the first polymer acceptor PD‐T‐Qx2CN. Subsequently, fluorine atoms are introduced at the para‐positions of the benzene rings at the 2,3‐positions of the Qx moiety, yielding the second acceptor, PD‐T‐FQx2CN. Notably, both polymer acceptors formed efficient bulk heterojunction networks with poly‐ polymer donor (3‐hexylthiophene (P3HT)). The P3HT:PD‐T‐FQx2CN‐based NIR PDs, owing to the affirmative contributions of the F substituent along the backbone, exhibited superior specific detectivities compared to the P3HT:PD‐T‐Qx2CN‐based PDs. The P3HT:PD‐T‐FQx2CN‐based NIR PDs exhibited excellent photoplethysmography (PPG) sensor properties. This research provides valuable insights into the structural‐property relationships of A1–π–A2‐type polymeric acceptors, aiding in the development of high‐performance all‐polymer NIR PDs. [ABSTRACT FROM AUTHOR]

AbstractFour compounds, [Zn4L2(HL)2](ClO4)2‧2H2O 1, [Zn4L2(HL)2](NO3)2‧2H2O 2, [Zn4L2(CH3COO)4]‧2H2O 3, and [Zn4L2(C(CH3)3COO)4] 4, have been obtained using a Schiff-base proligand, H2L, which was obtained from the condensation of 2,3-dihydroxybenzaldehyde with 2-(aminoethyl)pyridine. Their crystal structures have been solved by single-crystal X-ray diffraction. Compounds 1 and 2 feature {Zn4O6} cores with alternate mono- and bis-phenoxido bridges. Compounds 3 and 4 are constructed from L2- and carboxylato ligands, resulting in neutral linear tetranuclear species. TD-DFT calculations have been carried out to rationalize the electronic spectra of our complexes. The experimental luminescence spectra of the four complexes have been investigated in DMF solutions. [ABSTRACT FROM AUTHOR]

Intramolecular charge transfer (ICT) effects of para‐nitroaniline (pNA) in eight solvents (cyclohexane, toluene, acetic acid, dichloroethane, acetone, acetonitrile, dimethylsulfoxide, and water) are investigated extensively. The second‐order algebraic diagrammatic construction, ADC(2), ab initio wave function is employed with the COSMO implicit and discrete multiscale solvation methods. We found a decreasing amine group torsion angle with increased solvent polarity and a linear correlation between the polarity and ADC(2) transition energies. The first absorption band involves π → π* transitions with ICT from the amine and the benzene ring to the nitro group, increased by 4%–11% for different solvation models of water compared to the vacuum. A second band of pNA is characterized for the first time. This band is primarily a local excitation on the nitro group, including some ICT from the amine group to the benzene ring that decreases with the solvent polarity. For cyclohexane, the COSMO implicit solvent model shows the best agreement with the experiment, while the explicit model has the best agreement for water. [ABSTRACT FROM AUTHOR]

Fungal azaphilones are a broad class of naturally‐occurring pigments with diverse applications. Among the azaphilone pigments, mitorubrins are well recognized for their antiviral, antibacterial, antifungal, antiprotozoal, antidiabetic, and antiaging activities in addition to their well‐known yellow‐orange color. This makes these pigments interesting candidates for use in foods, as cosmetics, and as medicines. In particular, if it is desired to modify the properties of mitorubrin‐based pigments, for example by derivatization, it is essential to have an understanding of the electronic spectra of the parent molecules. We have therefore undertaken a computational study of a series of mitorubrins, comparing our computed results with experimental UV/visible spectra. Both density‐functional theory (DFT) and coupled‐cluster (CC2) methods have been used, and in general, the results are in very good agreement with observation. In order to provide a simple and useful picture of the spectra we analyze the stronger transitions in terms of natural transition orbitals (NTOs). [ABSTRACT FROM AUTHOR]

This study aims to describe the synthesis of a new class of selanylfullerene derivatives in a convergent strategy route, affording the desired products in a few steps and in good yields. C60 compounds were evaluated as photosensitizers to be used in photodynamic therapy (PDT) via the generation of singlet oxygen (1O2), using the chemical trapping method. The photooxidation of the chemical probe1,3‐diphenylisobenzofuran (DPBF) sensitized by selanylfullerenes followed a first‐order kinetic and the values of singlet oxygen quantum yields (ΦΔ) are appropriate for its use in PDT. The electronic absorption spectra, and the intersystem crossing tax rates for the most prominent synthesized compounds were calculated using the density functional theory and the Marcus electron transfer theory, with the theoretical results confirming the experimental findings. [ABSTRACT FROM AUTHOR]

Objective: This study aims to determine the structure of anthocyanins of common lilac flowers (Syringa vulgaris L.) of various color intensities and shades of lilac color from nine samples purchased at the Belgorod market by investigation of solute retention regularities of the compounds, peculiarities of their electronic absorption spectra as well as mass-spectra fixtures. Methods: Reversed-phase HPLC with a diode array as well as mass spectra detection by electrospray ionization with partial fragmentation were used. Results and Discussion: It was found that in all the studied samples the main component was delphinidin-3-rutinoside (84–90% by peak areas in the chromatogram). The level of cyanidin-3-rutinoside biosynthesis was significantly lower (6–19.6%). Among the minor compounds, delphinidin-3-glucoside and petunidin-3-glucoside were found. Among the unusual compounds, pyranoanthocyanin, built on the basis of delphinidin-3-rutinoside due to condensation with pyruvic acid, was found in a number of studied samples, but the reasons for its appearance have not yet been established. The total content of anthocyanins in the samples was rather low in the region of 0.020–0.120 g per 100 g of fresh material (depending on the color intensity of the original plant material) expressed as cyanidin-3-glucoside. Conclusions: By drying flowers on a cut branch, air-dried material was obtained containing 0.100–0.300 per 100 g of anthocyanins. [ABSTRACT FROM AUTHOR]

The rise of drug‐resistant infections highlights the critical need to discover novel drugs to combat them. In this study, we present the synthesis of a novel 2‐(aryl)‐5‐(3‐(difluoromethyl)‐1‐methyl‐1H‐pyrazol‐4‐yl)‐1,3,4‐oxadiazole compounds (3a–b) using benzohydrazide (1a–b) and 3‐(difluoromethyl)‐1‐methyl‐1H‐pyrazole‐4‐carboxylic acid (2). The structures of compounds were confirmed by FT‐IR, 1H‐NMR, 13C‐NMR, and HRMS characterizations. DFT calculations were performed using B3LYP/6–311G(d,p) method. The HOMO‐LUMO energy gap, reactivity parameters, and Mulliken atomic charges were determined and discussed. The electrostatic potential surface was mapped to identify active sites in compounds. The electronic absorption spectra were obtained in a chloroform solvent, and the Uv‐vis band assignments were discussed through TD‐DFT simulations. The results obtained from the experiment correspond well with the theoretical DFT analysis. The assessment of synthesized compounds (3a–b) antimicrobial properties is another aspect of the current investigation. Compound 3a was equally efficient as chloramphenicol against E. coli, P. aeruginosa, and S. pyogenes. However, limited antifungal activity was observed for both compounds. The Molinspiration ADME online tool examines drugs likeness properties. [ABSTRACT FROM AUTHOR]

This study investigates the effect of incorporating heavy dopant atoms on the topological transitions in the energy spectrum of graphene, as well as on its thermodynamic properties. A tight-binding model is employed that incorporates a lattice composition parameter associated with the dopant's effect to obtain the electronic spectrum of graphene. Thus, the substitutional atoms in the lattice impact the electronic structure of graphene by altering the connectivity of the Dirac cones and the symmetry of the energy surface in their spectrum. The Gibbs entropy is numerically calculated from the energy surface of the electronic spectrum, and other thermodynamic properties, such as temperature, specific heat, and Helmholtz free energy, are derived from theoretical principles. The results show that topological changes induced by the heavy dopant atoms in the graphene lattice significantly affect its electronic structure and thermodynamic properties, leading to observable changes in the distances between Dirac cones, the range of the energy spectrum, entropy, positive and negative temperatures, divergences in specific heat, and instabilities within the system. [ABSTRACT FROM AUTHOR]

Dark matter direct detection experiments are approaching the neutrino floor, with a significant probability of measuring coherent elastic neutrino-nucleus scattering (CEνNS) and exploring potential neutrino-related new physics (νNP). In the present study, the simultaneous presence of dark matter and νNP is emphatically investigated, revealing a response similar to Standard Model neutrino backgrounds in Xenon-based dark matter experiments. Through analyses of three U(1) extension models, it is determined that dark matter signals can be differentiated from an excess or a depletion of neutrino contributions from νNP by applying a statistically defined distinction method to nuclear and electronic recoil spectra. Additionally, an investigation is conducted into how νNP affects the exclusion limits for spin-independent dark matter-nucleon interactions. The present findings could facilitate the identification of new physics in future dark matter experiments. [ABSTRACT FROM AUTHOR]

A new cage-like dimeric nickel(II) complex Ni2L2(DMSO)4 based on a ditopic redox-active hydroxy-para-iminobenzoquinone type ligand LH2 (L is 4,4′-(1,3-phenylene-bis(azaneylylidene))-bis(3,6-di-tert-butyl-2-oxycyclohexa-2,5-dien-1-one dianion) was synthesized in DMSO at 120 °C. The molecular structure of the synthesized compound was determined by X-ray diffraction analysis. The complex Ni2L2(DMSO)4 is almost insoluble in all organic solvents, probably due to the presence of a large number of intermolecular contacts in its structure. The electronic spectrum and thermal stability of the crystalline compound have been studied. [ABSTRACT FROM AUTHOR]

Molecular and crystal structures of the novel [Pd{(PhO)2PS2}2] complex and the known [Pd{(EtO)2PS2}2] complex are studied. According to the XRD data, [Pd{(RO)2PS2}2] (R = Et, Ph) compounds crystallize in centrosymmetric space groups, and their crystal structures consist of mononuclear complex molecules. The and ions perform an S,S′-donor bidentate-chelating function leading to the formation of square-planar PdS4 coordination cores. The electronic absorption spectra of the solutions of these complexes are studied; the influence of the ligand structure and the solvent polarity on the observed optical properties of the studied compounds is considered. [ABSTRACT FROM AUTHOR]

The electronic structure of the strongly correlated electron system plutonium hexaboride is studied by using single‐particle approximations and a many‐body approach. Imaginary components of impurity Green's functions show that 5fj=5/2 and 5fj=7/2 manifolds are in conducting and insulating regimes, respectively. Quasi‐particle weights and their ratio suggest that the intermediate coupling mechanism is applicable for Pu 5f electrons, and PuB6 might be in the orbital‐selective localized state. The weighted summation of occupation probabilities yields the interconfiguration fluctuation and average occupation number of 5f electrons n5f ~ 5.101. The interplay of 5f–5f correlation, spin‐orbit coupling, Hund's exchange interaction, many‐body transition of 5f configurations, and final state effects might be responsible for the quasiparticle multiplets in electronic spectrum functions. Prominent characters in the density of state, such as the coexistence of atomic multiplet peaks in the vicinity of the Fermi level and broad Hubbard bands in the high‐lying regime, suggest that PuB6 could be identified as a Racah material. Finally, the quasiparticle band structure is also presented. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of different doping concentrations of O, Se, and Te atoms on the electronic structure and optical properties of single layer WS2 based on the density generalization theory of the first principles. The most stable structure. The system doped with Te atoms shows a shift from direct to indirect band gap, and the band gap of the system doped with Se atoms increases slightly. When investigating the optical properties, we also found that the absorption of light in each doped system mostly occurs in the ultraviolet region, and the absorption of light in the system doped with O atoms decreases, while the absorption of light in the system doped with Se and Te atoms changes with different frequencies. The reflectivity is higher than the intrinsic state. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of different doping concentrations of O, Se, and Te atoms on the electronic structure and optical properties of single layer WS2 based on the density generalization theory of the first principles. The most stable structure. The system doped with Te atoms shows a shift from direct to indirect band gap, and the band gap of the system doped with Se atoms increases slightly. When investigating the optical properties, we also found that the absorption of light in each doped system mostly occurs in the ultraviolet region, and the absorption of light in the system doped with O atoms decreases, while the absorption of light in the system doped with Se and Te atoms changes with different frequencies. The reflectivity is higher than the intrinsic state. [ABSTRACT FROM AUTHOR]

Breast cancer is a leading cause of cancer‐related morbidity and mortality among women globally. It arises from the abnormal proliferation of cells within breast tissue and can manifest in several subtypes, classified by the expression of hormone receptors. The main objective of this work is to assess the effect of solvent on 2‐methoxy‐4‐allylphenol's (2M4AP) in quantum chemical calculations and ability of 2M4AP to bind with the proteins associated with breast cancer. The non‐toxic nature of 2M4AP was initially validated through drug‐likeness studies and it complies with Lipinski's criteria. The optimization of 2M4AP structure was carried out in gas and liquid phase in DFT technique with B3LYP/6‐311++G (d, p) level. Then the electronic spectrum was calculated in TD‐DFT technique and the transition was determined to be n → σ*. The steadiness, charge dispersal and electronic properties were assessed and the band energy value was calculated to be 5.58 eV (gas) and 5.64 eV (liquid), exhibiting a stable confirmation of 2M4AP structure. Topological characteristics exhibited the intermolecular connections of 2M4AP along with electronic features. From the simulated results, the effect of solvent (water) in 2M4AP was very minimal and the structure is stable in both gas and liquid phase. Further, the docking studies, 2M4AP exhibited highest binding score of −7.3 kcal/mol with progesterone receptor, confirming the better ability of 2M4AP to react in hormone‐positive breast cancer. The Ramachandran plot confirms the stability of interacted amino acids with the ligand molecule. Thus, 2M4AP can be considered as a potent candidate for treatment of breast cancer after clinical studies. [ABSTRACT FROM AUTHOR]

A study of the solvent effect was used to describe the pronounced change in position of the UV-Visible absorption band associated with changing the polarity of the medium. Murexide compound which has different position of UV-Visible absorption band in the protic and nonprotic solvents. Various solvent parameters, such as dielectric constant, refractive index, Kamlet–Taft and Catalán parameters were used for the evaluation of the solute–solvent interactions and the solvatochromic shifts of the UV-Vis absorption maximum of the investigated indicator. The phenomenon of tautomerism is explained. The Kamlet–Taft solvent scale was found to be the most appropriate to describe the solvatochromic behavior of the Murexide. The dissociation constant pKa and the isosbestic point of the investigated compound showed the presence of the individual predominate ionic species in different pH ranges. [ABSTRACT FROM AUTHOR]

Two novel complexes were synthesized by the reaction of benzothiazol‐pyrimidin‐2‐ylidene ligand (BTP) with Pd (II) and Fe (III) ions. A variety of various spectral and analytical methods (infrared, 1H/NMR, 13C/NMR, electronic spectra, CHN analyses, mass spectra, thermogravimetric analysis, and magnetic susceptibility) were used to characterize the investigated BTP ligand and its complexes. Correlation of experimental results with density functional theory calculation proves that the geometry of BTP‐Fe complex is octahedral, whereas BTP‐Pd complex is square planner. The catalytic effectiveness of BTP complexes were tested for three‐component condensation process under moderate and environmentally friendly reaction conditions. Moreover, the effects of different Lewis acid, basic, and ionic liquid catalysts, as well as solvent and catalyst dose on the catalytic reaction were investigated. Both catalysts demonstrated strong catalytic capability in the carefully regulated ideal reaction circumstances. Heterogeneous catalyst BTP‐Pd exhibited superior catalytic performance compared to homogeneous catalyst BTP‐Fe. All products were obtained in high TOF (turnover frequency) numbers in the presence of these catalysts, which indicate the high efficiency of these catalysts in the synthesis of dihydro‐7H‐5‐thia‐hexaaza‐s‐indacen‐6‐one derivatives. Moreover, the two catalysts' recycling and reusability in reactions were also investigated. Heterogeneous BTP‐Pd catalyst could be reused up to seven times with high efficiency, but the homogeneous catalyst (BTP‐Fe) could only be recycled up to four times. Furthermore, the mechanism of catalytic reaction was suggested and supported by DFT calculation. The simplicity, safety, stability, use of commercially available catalysts, quick reaction times, and excellent yields make it promising for future industrial use. [ABSTRACT FROM AUTHOR]

In the current work, chloro(meso-tetrakis(phenyl)porphyrin) manganese(III) [Mn(TPP)Cl] was synthesized following two steps: the preparation of meso-tetraphenylporphyrin (H⁠2TPP) and the insertion of manganese into the free porphyrin H2TPP. The compounds were characterized using SEM, FT-IR, UV, TGA/DTA, and XRD analyses. Manganese(III) meso-porphyrins exhibited hyper-type electronic spectra with a half-vacant metal orbital with symmetry, such as [dπ:dxz and dyz]. The thermal behavior of [Mn(TPP)(Cl)] changed (three-step degradation process) compared to the initial H2TPP (one-step degradation process), confirming the insertion of manganese into the core of the free porphyrin H2TPP. Furthermore, [Mn(TPP)Cl] was used to degrade calmagite (an azo dye) using H2O2 as an oxidant. The effects of dye concentration, reaction time, H2O2 dose, and temperature were investigated. The azo dye solution was completely degraded in the presence of [Mn(TPP)(Cl)]/H2O2 at pH = 6, temperature = 20 °C, C0 = 30 mg/L, and H2O2 = 40 mL/L. The computed low activation energy (Ea = 10.55 Kj/mol) demonstrated the efficiency of the proposed catalytic system for the azo dye degradation. Overall, based on the synthesis process and the excellent catalytic results, the prepared [Mn(TPP)Cl] could be used as an effective catalyst for the treatment of calmagite-contaminated effluents. [ABSTRACT FROM AUTHOR]

In the present study, thirteen triphenylamine-based organic dye sensitizers with donor-p-acceptor patterns were created for utilization in dye sensitized solar cells (DSSCs). Theoretical computations such as DFT and TDDFT were employed to analyse the molecular structure of the dyes. Optimization was attained using the DFT/B3LYP approach with the 6-311++G (d,p) basis set to investigate structural and spectroscopic parameters. This study deals with the effect of different p-spacers. The electrochemical characteristics, electronic absorption spectra, energy levels, injection energy, light harvesting efficiency (LHE), frontier molecular orbitals, and dye generation energy were examined. All the created dyes are suitable for DSSC applications. The parameters such as low bandgap (2.30 eV), high light harvesting efficiency (0.972), strong oscillator strength, broad absorption spectrum and high electron injection energy made the dye P6 the best-performing one. [ABSTRACT FROM AUTHOR]

The the structural, electronic, and magnetic characteristics of the ZnSeS solid solution with manganese impurity have been evaluated within the DFT using the hybrid exchange-correlation functional PBE0. The structure of this solid solution was determined in two stages. At the first step the internal coordinates of atoms are optimized, and at the second one the lattice parameter relaxation, including reoptimization of internal coordinates, were done. Further, after the introduction of Mn substitution impurity, electronic energy spectra and the electronic DOS were obtained. Significant changes in parameters of the electronic structure and magnetic properties caused by the manganese impurity were found. It was established that the doped solid solution Mn:ZnSeS is a semiconductor for both electron spin polarizations. [ABSTRACT FROM AUTHOR]

Computational optimal transport is used to analyze the difference between pairs of continuous molecular spectra. It is demonstrated that transport distances which are derived from this approach may be a more appropriate measure of the difference between two continuous spectra than more familiar measures of distance under many common circumstances. Associated with the transport distances is the transport map which provides a detailed analysis of the difference between two molecular spectra and is a key component of our study of quantitative differences between two continuous spectra. The use of optimal transport for comparing molecular spectra is developed in detail here with a set of model spectra, so that the discussion is self-contained. The difference between the transport distance and more common definitions of distance is elucidated for some well-chosen examples and it is shown where transport distances may be very useful alternatives to standard definitions of distance. The transport distance between a theoretical and experimental electronic absorption spectrum for SO2 is studied and it is shown how the theoretical spectrum can be modified to fit the experimental spectrum better adjusting the theoretical band origin and the resolution of the theoretical spectrum. This analysis includes the calculation of transport maps between the theoretical and experimental spectra suggesting future applications of the methodology. [ABSTRACT FROM AUTHOR]

The electronic and vibrational spectra of the meso-tetrakis(4-sulfonatophenyl)-porphyrins (TSPP) have been studied computationally using the PFD-3B functional with time-dependent density functional theory for the excited states. The calculated UV-vis absorption and emission spectra in aqueous solution are in excellent agreement with the experimental measurements of both H2TSPP−4 (monomer) at high pH and H4TSPP−2 (forming J-aggregate) at low pH. Moreover, our calculations reveal an infrared absorption at 1900 cm−1 in the singlet and triplet excited states that is absent in the ground state, which is chosen as a probe for transient IR absorption spectroscopy to investigate the vibrational dynamics of the excited state. Specifically, the S2 to S1 excited state internal conversion process time, the S1 state vibrational relaxation time, and the lifetime of the S1 excited electronic state are all quantitatively deduced. [ABSTRACT FROM AUTHOR]

We report here investigations on conformational effects in the vibrational and electronic spectra of the propionaldehyde (propanal) molecule using FTIR (600–3200 cm−1) and vacuum ultraviolet (VUV) synchrotron radiation photoabsorption (52 500–85 000 cm−1) spectroscopy respectively. Detailed theoretical calculations (using DFT and TDDFT methodologies) on ground and excited states of the cis and gauche conformers of propanal are performed; a comprehensive spectral analysis of the IR and VUV spectra is presented. A reinvestigation of the IR spectrum reveals several new bands assigned to the gauche conformer based on theoretical calculations. The VUV spectrum exhibits rich Rydberg series structure assigned to ns, np and nd series converging to the first ionization potentials of the two conformers. Earlier assignments of the 3s cis and gauche origins are revised in addition to extending Rydberg series analysis to several higher members. Vibronic bands accompanying the 3s, 4s and 4p Rydberg states are assigned using estimated vibrational frequencies of cis and gauche conformers in the cationic ground state. Simulated potential energy curves of the first few excited states (singlets and triplets) of cis and gauche conformers of propanal help in gaining insights into photodissociation mechanisms and possible conformational effects therein. [ABSTRACT FROM AUTHOR]

We develop an accurate and numerically efficient non-adiabatic path-integral approach to simulate the non-linear spectroscopy of exciton–polariton systems. This approach is based on the partial linearized density matrix approach to model the exciton dynamics with explicit propagation of the phonon bath environment, combined with a stochastic Lindblad dynamics approach to model the cavity loss dynamics. Through simulating both linear and polariton two-dimensional electronic spectra, we systematically investigate how light–matter coupling strength and cavity loss rate influence the optical response signal. Our results confirm the polaron decoupling effect, which is the reduced exciton–phonon coupling among polariton states due to the strong light–matter interactions. We further demonstrate that the polariton coherence time can be significantly prolonged compared to the electronic coherence outside the cavity. [ABSTRACT FROM AUTHOR]

We present a theoretical study on the structural and electronic properties of the p-dimethylamino-cinnamaldehyde (DMACA) merocyanine molecule in solvents of different polarities by combining the free energy gradient and the average solvent electrostatic configuration methods via an iterative procedure based on the sequential quantum mechanics/molecular mechanics hybrid methodology. Studying such a system in solution is a crucial step for understanding the solvent effects on its properties, which can have implications in fields such as optoelectronics and biophysics. We found that the DMACA molecule presents different geometries in nonpolar and polar solvents, changing from a polyene-like structure with a pyramidal dimethylamino group (in gas phase or nonpolar solvents) to a cyanine-like structure with a planar dimethylamino group in water due to the stabilizing effect of hydrogen bonds between DMACA and water. The molecular absorption spectrum showed a significant change, increasing solvent polarity with a large shift of the lower energy band, while the other two low lying bands did not shift significantly. The study accurately described the solvatochromic shift of the lowest-energy band and analyzed the structure of the excited states in terms of the one-electron transition density matrix, which showed that the dominant excited state (associated with the first lower energy band) is characterized by a local excitation on the benzene ring with charge transfer character to the carbon conjugated segment. [ABSTRACT FROM AUTHOR]

New Schiff base ligand: 4-methoxy salicaldhyde-2-2-phenyl-hydrazono acetaldehíyde prepared by facile method. The molecular structures characterized by elemental analysis and proton magnetic resonance spectra (1H-NMR spectra). This spectra at the chemical shifts (3.5–10.39 ppm) confirmed the types and the numbers of protons. The sharp melting point at the range 110–112 °C confirmed purity. New optically active metal (samarium, terbium and gadolinium) complexes of the Schiff base synthesized in a one pot reaction. Vibrational IR spectra confirmed functional groups. Scanning electron microscopy micrographs confirmed that the modified microstructure of the metal complexes differed in morphology than the ligand. Powder X-ray diffraction patterns confirmed good crystalline structure. The optically activity of the solid metal complexes confirmed from electronic absorption spectra. The UV absorbance band at the wavelength range 280–390 nm and the intense phosphorescence bands up to 830 nm enabled application in photo dynamic therapy for apoptosis cancer cells by conversion triplet oxygen in the tissues into reactive singlet oxygen. Low charge transfer energy: 2.59–2.61 eV, high molar extinction coefficients (ε) at the order of magnitude M− 1 cm− 1 and the intense phosphorescence bands reflected good photodynamic activity. The metal complexes are thermally stable. [ABSTRACT FROM AUTHOR]

ABSTRACT This article explains the synthesis of three Schiff base Cu(II) complexes derived from 3‐hydroxybenzaldehyde and ethylenediamine using three distinct copper anionic salts, and it explores the effects of those salts on the properties of the complexes. Elemental analysis, electronic spectra, FT‐IR, ESR, molar conductance, magnetic measurement, thermogravimetric analysis and PXRD were used to characterize the compounds. The anionic salt has been demonstrated to exhibit distinctive characteristics on Gram‐positive and Gram‐negative bacteria in terms of structure, DNA binding, cell viability, DNA breakage and activity. Furthermore, this ligand L1 and its derivatives indicated positive antifungal efficacy against Aspergillus niger and Trichophyton tonsurans. The study elucidates the manner in which distinct anion salts impacted the properties of complexes and their antifungal, anticancer and antibacterial outcomes. [ABSTRACT FROM AUTHOR]