Frontier Molecular Orbital Analysis Research Articles

Repurposing of drug candidates against Epstein-Barr virus: Virtual screening, docking computations, molecular dynamics, and quantum mechanical study.

Epstein-Barr virus (EBV) was the first tumor virus identified in humans, and it is mostly linked to lymphomas and cancers of epithelial cells. Nevertheless, there is no FDA-licensed drug feasible for this ubiquitous EBV viral contagion. EBNA1 (Epstein-Barr nuclear antigen 1) plays several roles in the replication and transcriptional of latent gene expression of the EBV, making it an attractive druggable target for the treatment of EBV-related malignancies. The present study targets EBV viral reactivation and upkeep by inhibiting EBNA1 utilizing a drug-repurposing strategy. To hunt novel EBNA1 inhibitors, a SuperDRUG2 database (> 4,600 pharmaceutical ingredients) was virtually screened utilizing docking computations. In accordance with the estimated docking scores, the most promising drug candidates then underwent MDS (molecular dynamics simulations). Besides, the MM-GBSA approach was applied to estimate the binding affinities between the identified drug candidates and EBNA1. On the basis of MM-GBSA//200 ns MDS, bezitramide (SD000308), glyburide (SD001170), glisentide (SD001159), and glimepiride (SD001156) unveiled greater binding affinities towards EBNA1 compared to KWG, a reference inhibitor, with ΔGbinding values of -44.3, -44.0, -41.7, -40.2, and -32.4 kcal/mol, respectively. Per-residue decomposition analysis demonstrated that LYS477, ASN519, and LYS586 significantly interacted with the identified drug candidates within the EBNA1 binding pocket. Post-dynamic analyses also demonstrated high constancy of the identified drug candidates in complex with EBNA1 throughout 200 ns MDS. Ultimately, electrostatic potential and frontier molecular orbitals analyses were performed to estimate the chemical reactivity of the identified EBNA1 inhibitors. Considering the current outcomes, this study would be an adequate linchpin for forthcoming research associated with the inhibition of EBNA1; however, experimental assays are required to inspect the efficiency of these candidates.

Transition Metals Doped into g-C3N4 via N,O Coordination as Efficient Electrocatalysts for the Carbon Dioxide Reduction Reaction.

The electrochemical carbon dioxide reduction reaction (CO2RR) is a potential and efficient method that can directly convert CO2 into high-value-added chemicals under mild conditions. Owing to the exceptionally high activation barriers of CO2, catalysts play a pivotal role in CO2RR. In this study, the transition metal (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) is doped into g-C3N4 with a unique N,O-coordination environment, namely, TM-N1O2/g-C3N4. Herein, the catalytic performance and reaction mechanism for the CO2RR on TM-N1O2/g-C3N4 are systematically investigated by density functional theory methods. Especially, through the calculation of ΔG*H and ΔG*COOH/ΔG*OCHO, the catalysts with preference for the CO2RR over the hydrogen evolution reaction (HER) are selected for further study. Furthermore, Gibbs free energy computation results of each elementary step for the CO2RR on these catalysts indicate that Ti-N1O2/g-C3N4 has significant catalytic activity and selectivity for reducing CO2 to methanol (CH3OH) with the limiting potential (UL) of -0.55 V. Finally, through frontier molecular orbital theory and charge transfer analyses, the introduction of the O atoms illustrates that it is instrumental in regulating the electron distribution of the catalytic active site, thereby improving the catalytic performance. This work provides insight into the design of single-atom catalysts with unique coordination structures for the CO2RR.

Molecular modeling and cytotoxic activity studies of oxirane-2-carboxylate derivatives

In this study, five 3-aryloxirane-2-carboxylate derivatives were prepared, and the antiproliferative activities of molecules were screened in lung and colon cancer cell lines. The results showed that molecules had antiproliferative activity on cancerous cells with IC50 values under 100 µM. Furthermore, all of the molecules were found to have a much higher cytotoxic effect than cisplatin in colon cancer cells. The interactions of the relatively active compounds to the crucial enzyme in cancer cell proliferation, cyclin-dependent kinase 1 (CDK1), were investigated using molecular docking. The stability of the resulting CDK1-compound complexes procured from the docking was also assessed through molecular dynamics (MD) simulations. Then, the binding affinity of compounds 2-3a and 2-3c to the target enzyme was computed by MMPBSA. The molecular docking study demonstrated that the two most active compounds could bind to the enzyme. The binding potential of 2-3a is anticipated to be higher as it had one more conventional hydrogen bond and a slightly lower binding energy than compound 2-3c. The MD simulation study exhibited that the two compounds formed a stable complex with the enzyme. On the other hand, the MMPBSA energy computation implicated a slightly higher binding affinity for compound 2-3c toward the enzyme. Furthermore, electrical and frontier molecular orbital analysis of all of the tested compounds was conducted by density functional theory (DFT) studies. Compound 2-3a is anticipated to be the most chemically stable as it gave the highest energy gap value in the DFT analysis.

Electronic, thermodynamic, NLO, and spectroscopic properties of OAFLC compounds via DFT: A focus on 1F6B, 1F6Bi, 1F6BiN, and 1F6BN

This study presents a comprehensive quantum mechanical investigation of four novel liquid crystalline compounds: 1F6B, 1F6Bi, 1F6BiN, and 1F6BN. Using Density Functional Theory (DFT) with the B3LYP functional and 6-311G(d,p) basis set, we optimized the molecular geometries and analyzed their electronic and vibrational properties. Atomic Polar Tensor (APT) charge analysis showed significant charge distributions. Electrostatic potential (ESP) mapping identified potential reactive sites, while Electron Localization Function (ELF) and Localized Orbital Locator (LOL) analyses depicted the electron density distributions. Thermodynamic parameters indicated the compounds’ vibrational stability and responsiveness to thermal changes. Non-linear optical (NLO) properties were characterized by significant dipole moments and polarizabilities, suggesting potential in optoelectronic applications. Frontier molecular orbital analysis indicated stability with HOMO-LUMO gaps ranging from 4.15 to 4.64 eV. UV–Vis spectra revealed key electronic transitions, while Raman spectroscopy detailed various vibrational modes. The study offers valuable insights into the molecular behavior of these compounds, laying the groundwork for their future applications in material science and advanced technologies.

Facile Synthesis of (S)‐2‐Aryl‐N‐(1‐phenylethylisonicotinamides) Derivatives via SMC Reaction: Their Thermodynamic and Spectroscopic Features via DFT Approach

AbstractIn this study, 2‐bromoisonicotinic acid and (S)‐1‐phenylethaneamine were reacted in the presence of pyridine and TiCl4 to produce 2‐bromo‐N‐(1‐phenylethyl)isonicotinamide (3). The derivatives (5a–f) of (S)‐2‐bromo‐N‐(1‐phenylethyl)isonicotinamide were then created by a Suzuki–Miyaura cross‐coupling process catalyzed by palladium (0) and K3PO4 as a base. The reactivity and electronic features of the compounds were investigated using DFT molecular electrostatic potential investigations, reactivity descriptors, and frontier molecular orbital analysis.

Catalytic behavior, electronic structure and spectroscopic (FT-IR, Raman, UV–vis) properties for the new ionic liquid imidazolium hydrogen sulfate

Catalytic performance, chemical reactivity, vibrational modes and electronic transitions of the ion pair [H–Im]+[HSO4]– were investigated in the current paper. Hence, a combined experimental (Hammett acidity function, infrared, Raman and ultraviolet-visible spectroscopies) and theoretical (molecular electrostatic potential surface, reduced density gradient, frontier molecular orbital analysis, quantum theory of atoms in molecules, net atomic charges, global and local reactivity descriptors) study was conducted. In terms of the catalytic performance, the acetic acid esterification with butanol was evaluated. Important kinetic (rate constant, activation energy, pre-exponential factor) and thermodynamic (enthalpy, entropy, Gibbs free energy barrier) factors for ester production as a function of the temperature and catalyst loading have been determined. Results revealed intensive electron density distribution in [H–Im]+[HSO4]– due to chemical interactions between the cationic and anionic moieties. These bonds were established as electrostatic in nature. The pronounced charge transfers within [H–Im]+[HSO4]– managed the title compound acidity (H0) and its catalytic behavior towards butyl acetate synthesis. Using the thermodynamic and kinetic measurements, a mechanism for acetic acid esterification with butanol in the presence of imidazolium hydrogen sulfate ionic liquid was offered.

DFT study of electronic and nonlinear optical properties of alkaline earth metals and superalkalis doped all-cis-1, 2, 3, 4, 5, 6-hexafluorocyclohexane as an efficient excess electron system

Continual advancements are being pursued to discover innovative strategies for developing materials with remarkable nonlinear optical (NLO) response. Herein, electronic, geometric, thermodynamic and NLO properties of excess electron systems based on stacked Janus dimer, all-cis-1,2,3,4,5,6-hexafluorocyclohexane (C6H6F6)2 are thoroughly investigated. The excess electron systems are designed by doping alkaline earth metals (AEMs) on fluorine face and superalkalis on hydrogen face of Janus dimer. The higher values of vertical ionization energies (VIE) and interaction energies (Eint), confirm the electronic and thermodynamic stabilities of the designed complexes, respectively. Natural bond orbital (NBO) analysis is performed, and the excess electron character of the complexes is confirmed through frontier molecular orbital (FMO) analysis by highest occupied molecular orbital (HOMO) iso-densities. FMO shows a significant decrease in energy gaps (Egap) of the complexes (i.e., Eg = 1.80–3.12 eV), compared to the stacked Janus dimer (i.e., Eg = 9.41 eV). The transparency of the complexes to UV region is confirmed through UV–vis analyses, revealing their maximum absorption in visible and near-IR regions. The higher NLO response of the designed excess electron systems is further proved by the greater values of first hyperpolarizability (β o ) i.e., up to 1.70 × 106 au. Moreover, the time dependent-density functional theory (TD-DFT) computations and two-level model are employed to investigate the controlling factors of hyperpolarizability, illustrating the contribution of transition energy (∆E3), change in dipole moment (∆μ) and oscillator strength (f o ) in controlling the β o . Ab-initio molecular dynamics (AIMD) simulation further confirm that the designed superalkalide complexes are kinetically and thermally stable. The thorough investigation of these excess electron systems proves them an appropriate candidate for NLO applications.

TDDFT elucidating the PET-Inhibition Mediated fluorescence enhancement in a Cysteine probe

TDDFT has been used to confirm the cysteine-sensing mechanism of a reported fluorescent probe (Talanta, 2020, 220, 12136). Frontier molecular orbital analysis showed that the probe underwent a PET process from quinazolinone to acryloyl, which made the fluorescence quenched together with nonplanar structure. Cysteine removed the acryloyl moiety and inhibited the PET process. The planar geometry of the probe-cysteine product enlarged the conjugated system and enhanced the green fluorescence of the fluorophore. Moreover, the charge redistribution also led to the excited-state proton transfer process, ultimately enhanced the fluorescence intensity and a notable Stocks shift.

Experimental and theoretical studies of alkyl 2-(2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1]nonan-9-ylidene)hydrazine carboxylates: Synthesis, spectroscopic, crystal structure, Hirshfeld surface, and antimicrobial studies

The nine alkyl 2-(2,4,6,8-Tetraaryl-3,7-diazabicyclo[3.3.1]nonan-9-ylidene)hydrazine carboxylates having bicyclic bispidine core were synthesized and characterized using FT-IR, NMR, and mass spectra. Further confirmation of the structure and positioning of the groups was obtained using single crystal XRD investigation. The analysis revealed that one piperidine ring adopts a chair and another a boat form. The aryl groups in the chair conformation are positioned equatorially, whereas those in the boat conformation are orientated axially. The carbazate group (C=N-NH-COOR) aligned the center of the two piperidine rings, with a small deviation towards the boat conformation piperidine ring. The dihedral angle between the chair and boat conformations of the piperidine ring (2f) is 48.51 Å and 45.12 Å, respectively. Hirshfeld and 2D fingerprint analysis show considerable H···H bonding interactions in the crystal. The intermolecular interaction and mechanical stability of crystals were investigated using interaction energy and crystal void analysis. Reduced density gradient and localized orbital locator analyses were used to investigate intramolecular interactions and electron delocalization. The molecule's higher and lower electron densities were investigated utilizing frontier molecular orbital analysis and Molecular Electrostatic Potential. The antimicrobial activity of the compounds was investigated using four bacterial and two fungus strains.

Synthesis, in vitro antibacterial and antioxidant evaluation, DFT calculation, molecular docking, and ADMET studies of novel N-Acyl-6-chloro-2(3H)-benzoxazolone derivatives

A new series of N-acyl-6-Chloro-2(3H)-benzoxazolone derivatives (4a-4g) were synthesized using an eco-friendly catalyst. The compounds were characterized using spectroscopic techniques, including FTIR, 1H NMR, 13C NMR, and GC–MS. Their antimicrobial activity against various bacterial strains, including both Gram-negative and Gram-positive bacteria, was evaluated and yielded promising results. The synthesized compounds were also tested for their antioxidant properties using the DPPH radical-scavenging method, where compound 4f exhibited the highest activity with an IC50 of 1.54 μg/mL, surpassing that of ascorbic acid (IC50 = 1.7 μg/mL). Additionally, DFT calculations were performed to investigate the compounds’ chemical reactivity, including the analysis of HOMO and LUMO frontier molecular orbitals, global reactivity descriptors, and molecular electrostatic potential. Molecular docking studies were conducted to explore the interactions between the synthesized compounds (4a-4g) and the standard drug ciprofloxacin at the active site of DNA gyrase. Furthermore, physicochemical properties, lipophilicity, water solubility, pharmacokinetics, drug-likeness, and medicinal chemistry properties were estimated using SwissADME. Toxicological profiles, including hepatotoxicity, carcinogenicity, immunotoxicity, mutagenicity, cytotoxicity, and LD50, were predicted using the ProTox-III web tool. The findings suggest potential therapeutic applications for combating bacterial strains, indicating that these synthesized compounds could serve as lead compounds for antibiotic drug development.

Synthesis, vibrational, thermal, topological, electronic, electrochemical stability and DFT studies of new DABCO based ionic liquids

The design of new ILs with different anions could provide interesting physico-chemical properties and for these reasons, the knowledge about the synthesis, the thermal, vibrational, topological, electronic, electrochemical properties and interaction between the selected cation-anion in these ILs are important subjects. Therefore, the understanding about these properties of these compounds is an important subject of study. In this work, we studied three ionic liquids based on the 1-decyl-1,4-diazabicyclo[2.2.2]octane, DABCO-cation, where the corresponding anions were [Br]-, [PF6]-, and [N(SO₂CF₃)₂]-. The syntheses of these bicyclic DABCO ionic liquids are based on an alkylation reaction of 1,4-diazabicyclo[2.2.2] octane and 1-bromodecanefollowed by anion exchange. The obtained ILs are characterized by 1H, 13C, 19F and 31P-NMR spectroscopy. Vibrational spectroscopy studies are conducted by infrared (FTIR/ATR) and Raman spectroscopy in the wavenumber range 600–4000 cm-1 and 45–3500 cm-1, respectively. Furthermore, the thermal stabilities were investigated using the thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) methods. Results indicate that the thermal stability follow the order [C10DABCO][Br]<[C10DABCO][PF6]<[C10DABCO][N(SO₂CF₃)₂]. Additionally, the structural parameters, electrostatic potential (ESP) maps, interaction energies, non-covalent interaction (NCI), atoms in molecule (AIM) analysis, natural bond orbital (NBO), frontier molecular orbital (FMO) analysis and Electrochemical window (ECW) are studied and analyzed by means of DFT calculations at the M06–2X-GD3/AUG–cc–pVDZ level of theory.

Computational investigation into the structure, effect of band gap energies, charge transfer, reactivity, thermal energies and NADPH inhibitory activity of a benzimidazole derivative

This work contains computational investigations of a benzimidazole derivative consisting of density functional theory, electronic structure and biological evaluation of a benzimidazole derivative. Density functional theory evaluation were conducted, starting from geometry optimisation, followed by the molecular electrostatic potential, spectral analyses, polarizability studies and thermodynamic analyses via the frequency calculations. Solvent frontier molecular orbital analyses, impact on the properties of the molecule were modelled with the IEFPCM model of solvation. Topological analyses helped to ascertain the molecule’s electronic structure. Biological assessment included pharmacokinetic property evaluation and molecular docking. Pharmacokinetic descriptors were generated using online tools and the molecule was assessed for its efficacy as a drug molecule by comparing with the rules concerning drug-likeness and analysing the descriptors relating to absorption, distribution, metabolism, excretion and toxicity of the molecule. Docking of the molecule with the two targets, 7D3E and 3A1F, yielded a good binding energy of −7.39 and −5.81 kcal/mol respectively.

Alpha-Glucosidase Inhibitory Effects of Flavonoids, Phenolic Acids and Iridoids Isolated From Vinca Soneri: In Vitro and In Silico Perspectives.

Various Vinca species have been traditionally used for their antihypertensive, sedative, and hemostatic properties, as well as for treating diabetes. In this study, some flavonoids, phenolic acids and iridoids were isolated from an endemic Vinca species, Vinca soneri for the first time. α-Glucosidase inhibitory effects of the isolates were tested and kaempferol-3-O-α-rhamnopyranosyl (1→6) β-galactopyranoside (1) was found to be the most active one with an IC50 value of 285.73 ±7.35 μM. Enzyme kinetic assay revealed that it inhibited α-glucosidase in competitive manner. Molecular geometry of 1 was predicted and Frontier molecular orbital analysis was performed using Density Functional Theory (DFT) calculations. Molecular docking and MM-GBSA calculations predicted good fit for 1 in the enzyme active site and key interactions with the catalytic residues. As a result, current study identifies 1 as a promising competitive α-glucosidase inhibitor to be developed as a potential antidiabetic drug candidate.

Molecular engineering on tyrian puprle natural dye as TiO2 based fined tuned photovoltaic dye material: DFT molecular analysis

In this research, molecular modification is employed to see the enhancement in the efficiency of Tyrian Purple (TP), a natural dye, for organic photovoltaic materials.By using Density Functional Theory (DFT) based molecular modeling, seven new structures are designed with pi spacer to extend electron donor moieties. Teheir Frontier Molecular Orbital (FMO) analysis demonstartes their charges with a similar pattern of distributions over their Highest Occupied and Lowed Unocuupied Molecular Orbitals (HOMO/lUMO). This analysls also show their energy gaps (Egaps) to range around 2.97-3.02 eV. Their maximum absorption wavelength (λmax) demosntartes 486-490 nm range to indicate their tendency of absorbing light efficiently. Their Transition Density Matrix (TDM) analysis also reveals their facile electronic transitions without a significant charges over spacers. From calculating their photovoltaic paramters, their Light Harvesting Efficiency (LHE) reaches to 72.4-95.5 %. Also their Open Circuit Voltage (Voc) varies across 1.16-1.34 V. It is found that dyes actively adsorb onto TiO2 clusters to demonstrate their promise for tuning their Conduction Band (CB). This research is an effort for to evaluate the structural correlations to the developm photovoltaic materials through molecular-level design and optimization.

Finely tuned energy gaps in host-guest complexes: Insights from belt[14]pyridine and fullerene-based nano-Saturn systems

Over the past few decades, doping, physisorption and chemisorption remained some of the commonly utilized methods to modify the energy gaps and electronic properties of materials. Yet, achieving precise control over tuning the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels within these systems persisted as a remarkable challenge. Therefore, there is a growing need for systems that facilitate exact adjustments of energy gaps and HOMO/LUMO levels. Here, in this research work, the nano-Saturn host-guest complex systems are designed based on belt[14]pyridine as a host and fullerene nanocages (C20, C32, C34 and C36) as guests. The greater thermodynamic stability of the complexes is revealed by the higher values of interaction energies (Eint) for these complexes, ranging from −45.50 to −56.81 kcal/mol. The frontier molecular orbital (FMO) analysis revealed the contribution of HOMO of fullerenes and LUMO of belt[14]pyridine towards the HOMO and LUMO of the designed complexes, respectively. The energy gaps of the complexes also decrease compared to the constituents, with the least Egap of 0.52 eV observed for C20@N-belt. Moreover, the charge transfer from the host towards the guests is predicted and confirmed via natural bond orbital (NBO) and electron density difference (EDD) analyses. The non-covalent interaction index (NCI) and quantum theory of atoms in molecules (QTAIM) analyses determine the nature and strength of interactions in the host-guest complexes. Moreover, it is noticed through the UV–vis analysis that the bare fullerenes show the maximum absorption in ultraviolet (UV) region, but after complexation, maximum absorption is observed in visible and near infrared (NIR) regions, with highest λmax of 927 nm for C36@N-belt. These findings highlight the successful development of nano-Saturn host-guest complexes with precise control over HOMO-LUMO levels and energy gaps. This work aims to address the challenges in fine-tuning the electronic properties and demonstrates potential applications in optoelectronics, photovoltaics, and NIR-based sensors. Moreover, the ability to tune the electronic properties can guide future material design strategies for advanced energy storage and photonic devices.

Isatin-Fluorene Schiff base as potent antidiabetic agent: Synthesis, DFT calculations, Topology, in silico ADME analysis and molecular docking studies

Diabetes mellitus is a rapidly evolving planetary challenge with substantial societal, salubrity, and financial connotations. Derivatives of isatin with hydrazides, coumarin and aldehydes have proven to possess anti-diabetic activities. Hence, as a novel perspective, isatin was merged with a polycyclic aromatic compound, 2-amino fluorene to build a Schiff base compound with anti-diabetic activity. The anti-diabetic characteristics of the designed compound were scrutinised through in silico molecular docking studies. The designed compound, (Z)-3-((9H-fluoren-2-yl)imino)indolin-2-one (FII) was synthesised in the laboratory using a simple condensation procedure. NMR, HRMS, and Infrared spectral analyses did the experimental structural characterisation of FII. The theoretical investigations of FII were evaluated via density functional theory (DFT). The DFT studies provide insight into the structure, reactivity, and electronic properties of compound FII. The most stable conformation of FII was identified and confirmed by the B3LYP method. The basis set 6-31+G(d) was used for the calculations. The DFT studies include frontier molecular orbital (FMO) analysis to define the global parameters and molecular orbital energy gap, molecular electrostatic potential (MEP) map to find out the reactive sites and natural bond orbital (NBO) analysis for understanding the electron density and charge delocalisation of the title compound, FII. Topological analyses such as ELF, LOL, RDG, and QTAIM were performed to investigate the electronic bonding parameters. Additionally, UV-visible and photoluminescence spectra were performed to investigate the optical properties of FII. The biological potential of the title compound was validated by calculating the physicochemical properties using Lipinski's rule. The molecular docking of the synthesised compound, FII, has been computed using two different proteins, exhibiting inhibitory activity against the α-Glucosidase enzyme. The binding energy and ligand efficiency of both the selected proteins with the ligand molecule were also calculated.

Preferred Electric Field Mechanism for Frustrated Lewis Pair Reactivity.

This study employs computational methods to investigate the mechanism of H2 activation by frustrated Lewis pair (FLP) species, including both intermolecular and intramolecular nitrothane/borane FLP systems. Previous studies have proposed two qualitative reactivity mechanism models to explain the facile cleavage of H2 by FLPs. The findings of this study support the electric field mechanism as the favorable pathway for H2 cleavage. Utilizing frontier molecular orbital theory and energy decomposition analysis, the study explores the electronic structure and nature of the reactions under an external electric field (EEF). Analysis using the activation strain model highlights the significant influence of geometrical deformation energies of FLPs on the activation barriers of H2 activation reactions. Computational results suggest that H2 activation by FLP molecules follows the electric field mechanism, indicating the potential of the FLP/EEF combination as an effective activator for inert molecules.

Tuning optoelectronic properties of indandione-based D-A materials by malononitrile group acceptors: A DFT and TD-DFT approach.

Indandione-based materials are promising candidates for organic electronics, offering high electron mobility and tunable optoelectronic properties. In this study, we explore the optoelectronic and photovoltaic properties of indandione-based donor-acceptor (D-A) materials, specifically (R1) and (R2), by introducing malononitrile group acceptors into their molecular structure. These strong electron-withdrawing acceptors are designed to enhance charge transfer and overall material performance. The designed molecules (DM1-DM4) exhibit a low optical band gap of approximately 1.77eV, significantly lower than the reference materials (R1 and R2) at around 2.24eV in a solvent environment. Among the designed molecules, DM4 stands out with superior photovoltaic parameters, including a narrow optical band gap (1.77eV), higher electron affinity (3.49eV), an extended excited state lifetime (10.0ns) owing to its low electron and hole reorganization energies (λe ~ 0.13eV and λh ~ 0.24eV), and improved short-circuit current density (Jsc) of ~ 15.73mA/cm2. Notably, DM4 achieves a power conversion efficiency (PCE) of ~ 18.5%, making it an excellent candidate for device applications. A comprehensive computational investigation was carried out on indandione-based D-A materials with malononitrile group acceptors (DM1-DM4) using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods, as implemented in Gaussian 16 software. We examined the electronic and optical properties of the proposed molecules through frontier molecular orbital (FMO) analysis, UV-Vis absorption spectra, density of states (DOS), exciton binding energy (Eb), and transition density matrix (TDM) analysis, utilizing GaussView 6.0 and Multiwfn 3.8 software. The photovoltaic parameters and power conversion efficiency (PCE) were evaluated using the Scharber and Alharbi models.

Theoretical and experimental investigation of mixed-ligand metal(II) Schiff base complexes using maleic acid as the auxiliary ligand

This work is focused on the synthesis of several transition metal complexes [ML(MA)], where M = Copper (II), Zinc (II), Cobalt (II) and Nickel (II), MA = maleic acid and L = Schiff base generated from benzene-1,2-diamine [o-phenylenediamine] and 4-chlorobenzaldehyde. The characterization using Fourier-Transform Infrared, Nuclear Magnetic Resonance spectroscopy, Ultraviolet-Visible spectra, Mass, Electro Paramagnetic Resonance and elemental analysis confirm the square planar geometry of the complexes. The in vitro antimicrobial potential of the complexes has been tested by the broth dilution method and the antioxidant method has been done by free radical scavenging analysis. The in vitro methods reveal the outstanding biological characteristics of the copper complexes. The molecular structure of the ligand and its metal (II) complexes has been optimized using Density Functional Theory studies performed by the Gaussian-09 software and their parameters have been discussed. Natural Bond Orbital and Frontier Molecular Orbital analyses have assessed the presence of a metal-ligand bond in complexes. In addition, molecular docking studies have also been performed on antiviral activity of all the complexes using a viral protein and their interacting amino acids.

Rational analysis of hydrogen bonding interaction in phenazine, 2-hydroxynaphthalene (1:1) cocrystal: from molecular modeling to photophysical properties.

Organic cocrystals have a wide range of applications in the field of optics due to their photo responsive property. We present here a newly synthesized phenazine 2-hydroxynaphthalene (1:1) cocrystal, its structural and theoretical calculations which tend to the nonlinear optical property. In the crystal structure of the title cocrystal, the phenazine and 2-hydroxynaphthalene molecules from one- and two-dimensional supramolecular frameworks via O‒H…N hydrogen bonds and C‒H…N, C‒H…π interaction, respectively. The phenazine molecules from an infinite off-set stacking through π…π interactionin the three-dimensional molecular packing of the title cocrystal. The contribution of intermolecular interaction in the three-dimensional molecular packing and the interaction energy calculation is studied by the Hirshfeld surface analysis. The molecular geometry retrieved from the experimental X-ray diffraction analysis is in good agreement with the theoretically calculated parameters. Further, the molecular electrostatic potential (MEP) and frontier molecular orbital (FMO) analysis have been carried out to study the charge distribution and molecular reactive mechanism. Third-order nonlinear optical property of the cocrystals has been analyzed by Z-scan measurements. The determined nonlinear optical absorption coefficient value 6.442 × 10-05 (m/W) and the nonlinear refractive index value - 5.535 × 10-2 (m/W) suggest that the crystalline solid can be a good choice of potential nonlinear optical material. The crystal structures of phenazine 2-hydroxynaphthalene cocrystal was solved by direct methods procedure using SHELXS program and refined by full-matrix least square procedure on F2 using SHELXL-2018 program on Olex2 software. The computational calculation has been carried out using DFT/B3LYP quantum chemical function with triple zeta 6-311 + + basis set in the ground state molecular stability using Gaussian 09W program suite. The Hirshfeld surface analysis mapping, associated 2D fingerprint plot, and intermolecular molecular interaction energy calculations were carried out using CrystalExplorer (version 21.5) software.