Frontier Molecular Orbitals Research Articles

Adsorption Effects of Isoniazid Drug Over Carbon Nanotube (C56H16) and Ab‐Initio Molecular Dynamics Simulation (ADMP) – A Computational Quantum Chemical Approach

AbstractTuberculosis (TB) is a deadly disease of global concern. The previous work studies the geometric optimization, vibrational analysis, TDDFT, and electronic properties of the TB pathogen drug isoniazid (ISO). This communication will discuss the changes in geometry, electronic properties, and shielding parameters of ISO‐absorbed carbon nanotube (CNT) (CNT‐ISO, C56H16). This study has used the DFT/B3LYP/6–311G (d, p) method for the first time to report ISO's electronic structure and interaction parameters on the CNT surface. The same level theory is used to discuss the thermodynamic stability of CNT‐ISO. The calculated UV spectra of CNT are compared with UV spectra of CNT‐ISO by using the same level theory in a water solvent, which provides a better comprehension of CNT as a drug delivery system after absorption of the ISO in the human body. The nature and strength of interactions have been discussed with the help of NBO and AIM analysis, and the frontier orbital highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO‐LUMO) gap, chemical softness, and chemical hardness have been calculated to understand its complete chemical properties. The characters of the frontier molecular orbitals are discussed and analyzed by comparing the DOS spectra of CNT with CNT‐ISO. It has also examined the scan plot of interaction with time using ab‐initio dynamics simulation (ADMP) calculations.

Structure-property relationship of two gamma-lactam derivatives: Hirshfeld surface analysis, DFT, and molecular dynamics simulations

Complete structural and non-covalent interactions of 2a and 2b are examined by single crystal X-ray diffraction and computational studies. Hirshfeld surface analysis showed differences in the relative contribution of non-covalent interactions of 2a and 2b. Fingerprint plots recognize the major contribution of H…H contacts in 2a and 2b. Density functional theory using implicit solvation models, the energy gap of the frontier molecular orbitals found to be 4.624 eV in 2a and 4.264 eV in 2b. Docking studies predicted that 2a and 2b have suitable structures to target Human Topoisomerase II Alpha, which was further validated using MM/GBSA and MDSs studies.

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.

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.

Heteroleptic complexes of hydrazone Scaffold of picolinoyl N- oxide and 2,4 dihydroxy phenyl moieties; evaluation of antioxidant activity, DNA and protein binding properties and in vitro antiproliferation studies

The present study deals with design and synthesis of new mononuclear Cu(II), Co(II), Ni(II) and Zn(II) metal complexes of hydrazone of 2-(2-(2,4-dihydroxybenzylidene)hydrazinecarbonyl)pyridine-1-oxide (H2L), in a view to study their potential relevance for the biological applications. Structural aspects of the title compound (H2L) and metal complexes synthesized were evaluated by spectral and analytical methods viz. 1H NMR, 13C NMR, LC-MS, FT-IR, UV–Visible, SEM, EDX, Powder XRD, ESR, TGA and DTA. Ligational properties of H2L were explored by employing pH metric equilibrium studies for recognizing metal ion binding potential donor sites, and further HyperChem 7.5 software for computing properties of frontier molecular orbitals to ascertain orientation of highest occupied molecular orbitals from which presumably electrons are donated to metal ion in complex formation. The affinity of all title compounds to bind with CT-DNA and the type of interaction, therein have been studied by conducting UV–VIS absorption and fluorescence emission titrations. The protein-binding ability of all metal complexes with two serum proteins (BSA and HSA) were explored by absorption titrations, and further fluorescence titrations for BSA binding were also performed. Antioxidant activity of the title compounds was carried out by the method of free radical scavenging using spectrophotometric technique. Additionally, cytotoxicity of all metal complexes and ligand was measured by CTG cell proliferation assay after treating them with MDA-MB-231 and SKOV-3 cell lines. The cell cycle arrest and apoptosis assay in above cell lines after treatment with title compounds were also investigated by flow cytometry. In addition, molecular docking studies at target CDK2 protein inferred binding affinity of the title compounds through non covalent bonding interactions.

Synthesis of a new quaternary ammonium salt for efficient inhibition of mild steel corrosion in 15 % HCl: Experimental and theoretical studies

The corrosion phenomenon and its economic impacts can hardly be ignored in any application. This study synthesized a quaternary ammonium salt (3) containing hydrophobic dodecyl and electron-rich diallylbenzyl amine moieties to be used in 15 % HCl as a corrosion inhibitor of mild steel. Several techniques, such as 1H and 13C NMR, IR, TGA, and elemental analysis, have been used to characterize inhibitor 3. Popular corrosion measurement techniques, namely weight loss, potentiodynamic polarization techniques, and electrochemical impedance spectroscopy, have been used to determine the efficiency of inhibitor 3. At 303 K and a moderately low concentration of 50 ppm, the quaternary ammonium salt-based inhibitor demonstrated a maximum efficiency of ≈95.0 %. At elevated temperatures of 313, 323, and 333 K, the inhibition efficacy values were recorded as 91.3, 82.8, and 75.0 %, respectively. Adsorption isotherm study revealed that the adsorption of inhibitor 3 followed Langmuir adsorption isotherm. The value of ΔGads° was found to be – 40.19 kJ mol−1, indicating that inhibitor 3 became adsorbed via a mixed physi-chemisorption mechanism. A very high adsorption constant (Kads) of 1.53 × 105 L mol−1 suggested strong adsorption of inhibitor 3. The difference in activation energy (Ea) value of 42.4 kJ mol−1 between the control and the inhibited solution indicated an efficient adsorption of inhibitor 3. The ability of inhibitor 3 to retard both anodic and cathodic half-cell reactions was proved via open circuit potential and Tafel curves studies. Detailed discussions on the change in corrosion current densities (icorr), polarization (Rp) and charge transfer (Rct) resistances have been offered to discuss the inhibition efficiency. Water contact angle measurement showed a drastic increase in mild steel surface hydrophobicity following inhibitor 3 adsorption. SEM-EDX and XPS studies confirmed the definitive presence of inhibitor 3 on the mild steel surface. Density functional theory (DFT) studies revealed the frontier molecular orbitals with which the metal surface interacts. A detailed corrosion inhibition mechanism has been offered in the context of adsorption isotherm and DFT studies.

Copper(II) and Zinc(II) complexes of new water-soluble Schiff base ligands and their antiproliferative properties towards mesothelioma cell line

In this work, three Schiff base ligands (HL1-HL3) containing a triphenyl phosphonium cation and their Cu(II) and Zn(II) complexes with the general formulae of [M(L)Cl2] were synthesized and their structures were characterized by spectroscopic and analytical methods. Crystal structure of complex [Zn(L1)Cl2] was determined. In the structure of the complex, each Zn(II) ion is four coordinated binding to phenolate oxygen and imine nitrogen atoms of the ligand L1 and two chloride atoms in approximately tetrahedral geometry. The equilibrium geometry of three Schiff base ligands (HL1-HL3) and their Cu(II) and Zn(II) complexes were calculated using the density functional theory (DFT/B3LYP) method with the 6–31++G(d,p) basis set for the C, H, Cl, N, O, P atoms and LANL2DZ for the I atom. Frontier molecular orbitals (HOMO, LUMO) analyses were conducted for the optimized geometries of the compounds, and chemical reactivity descriptors such as hardness, softness, electrophilicity, and electronegativity were examined. Additionally, the molecular electrostatic potential (MEP) of all compounds was modeled using DFT calculations. These calculations were thoroughly examined, and their implications were discussed. The ligands and their metal complexes were investigated for their DNA binding properties. The compounds showed comparable DNA binding properties to ethidium bromide (EB) and 5-fluorouracyl (5-Fu) with DNA binding constant (Kb) 1.5–6.25 × 105 M−1. The cytotoxic properties of the compounds towards HUVEC and H2452 (mesothelioma cell line) cells were investigated using an MTS assay. The IC50 values determined for HUVEC cells were found to range between 27.28 µg/mL ([Cu(L2)Cl2]) and 273.1 µg/mL ([Zn(L2)Cl2]), while in H2452 cells, they varied from 39.48 µg/mL ([Cu(L2)Cl2]) to 319.3 µg/mL ([Zn(L3)Cl2]). The compounds HL1, HL3, and [Zn(L3)Cl2] exhibited antioxidant activity at the highest concentration (750 µg/mL) only, while [Zn(L1)Cl2], HL2, [Zn(L2)Cl2], [Cu(L2)Cl2], and [Cu(L3)Cl2] showed antioxidant activity at 250 µg/mL.

Correlating Chemical Structure and Charge Carrier Dynamics in Phenanthrocarbazole‐Based Hole Transporting Materials for Efficient Perovskite Solar Cells

ABSTRACTPolymeric hole transport materials (HTMs) have emerged because of their potential to produce dopant‐free, efficient, and stable perovskite solar cells (PSCs). Therefore, we engineered 10 novel donor materials (SMH1–SMH10) containing phenanthrocarbazole‐based polymeric structures for organic and PSCs. These molecules underwent bridging‐core modifications using different spacers, such as furan (N1), pyrrole (N2), benzene (N3), pyrazine (N4), dioxane (N5), isoxazole (N6), isoindole (N7), indolizine (N8), double bond (N9), and pyrimidine (N10), in comparison to reference molecule R. The study examined the structure–property relationship and the impact of these modifications on the optical, photovoltaic, photophysical, and optoelectronic characteristics of the newly designed SMH1–SMH10 series. Density functional theory (DFT) and time‐dependent density functional theory (TD‐DFT) calculations were conducted to analyze frontier molecular orbitals, density of states, reorganization energies, open‐circuit voltage, transition density matrix, and charge transfer processes. Results show that the newly designed molecules (SMH1–SMH10) exhibited superior optoelectronics characteristics compared to the R molecule. Among these, SMH4 is the most promising candidate, with a small band gap (2.79 eV), low electron and hole mobility (λe 0.0028 eV, λh 0.0020 eV), lower binding energy (Eb 0.58 eV), high λmax values (656.42 nm in gas, 573.34 nm in chlorobenzene), and a high Voc of 1.30 V. Therefore, this study demonstrated that bridging‐core modifications offer a simple and effective strategy for designing desirable characteristics molecules for photovoltaic applications.

IPr# Complexes-Highly-Hindered, Sterically-Bulky Cu(I) and Ag(I) N-Heterocyclic Carbenes: Synthesis, Characterization, and Reactivity.

Metal-N-heterocyclic carbene (M-NHC) complexes are well-known as an important class of organometallic compounds widely used in transition-metal catalysis. Taking into account that the steric hindrance around the metal center is one of the major effects in M-NHC catalysis, the development of new, sterically hindered M-NHC complexes is an ongoing interest in this field of research. Herein, we report the synthesis and characterization of exceedingly sterically hindered, well-defined, air- and moisture-stable Cu(I) and Ag(I) complexes, [Cu(NHC)Cl] and [Ag(NHC)Cl], in the recently discovered IPr# family of ligands that hinge upon modular peralkylation of anilines. The complexes in both the BIAN and IPr families of ligands are reported. X-ray crystallographic analyses and computational studies were conducted to determine steric effects, Frontier molecular orbitals, and bond orders. The complexes were evaluated in the model hydroboration of the alkynes. We identified [Cu(BIAN-IPr#)Cl] and [Ag(BIAN-IPr#)Cl] as highly reactive catalysts with the reactivity outperforming the classical IPr and IPr*. Considering the attractive features of well-defined Cu(I)-NHC and Ag(I)-NHC complexes, this class of sterically bulky yet wingtip-flexible complexes will be of interest for catalytic processes in various areas of organic synthesis and catalysis.

Aqueous extract of CAP-ash: A greener benchmark for Suzuki-Miyaura coupling reaction in palladium catalyzed ligand-free condition

Synthesis, molecular, spectroscopic properties, and electronic structure calculations of biphenyls derivatives have been achieved using a highly efficient catalytic amount of Pd(OAc)2 in aqueous extract of custard apple peels (CAP)-ash (AECAP) a green, highly cost-effective, operationally convenient and environmentally benign media at ambient temperature. The analytical reports showed the presence of metal oxides which are probably extracted in water produces corresponding hydroxides, which provide alkaline media in water which shows dual performance (solvent and base) for said cross-coupling transformation. The catalytic system is generated in situ based on aqueous extract and Pd(OAc)2 which requires no external base and ligand. Moreover, the study also offers insights into the frontier molecular orbitals (FMO), electronegativity, chemical potential, global electrophilicity index, ionization potential, electron affinity, chemical hardness, and softness properties of the synthesized biphenyl derivatives for understanding their stability, active sites, and biological activity using density functional theory (DFT) at the B3LYP/6–311G(d,p) level/basis.

Exploring the interaction of Cu-modified B12N12 nanocages for Favipiravir drug delivery using density functional theory study

Drug delivery has become a pivotal strategy in medical research, aiming for precise delivery near cells while minimizing unwanted effects. In this study, we have used density functional theory (DFT) calculations at the B3LYP/6-311G(d,p) basis set to explore the potential of Cu-modified boron nitride (B12N12) nanocages as smart nanocarriers for delivering the Favipiravir (FAV) drug. This study examined the adsorption energy, electronic features, and thermodynamic properties (ΔG and ΔH) of FAV with B12N12 and Cu-modified B12N12 nanocages, revealing enhanced drug-delivery capacity with notable physisorption and negative adsorption energies. A comprehensive analysis confirmed FAV’s interaction with Cu-modified B12N12 nanocages, involving frontier molecular orbitals, adsorption energy, fractional charge transfer, molecular electrostatic potential (MEP), non-covalent interaction (NCI), and natural bond orbital (NBO) assessments. The analyses of frontier molecular orbitals (FMO), partial density of states (PDOS), and natural bond orbital (NBO) indicate that nanocages act as charge acceptors, while the drug acts as a charge donor during the adsorption process. Among the various Cu-modified B12N12 nanocages studied, Cu-doped CuB11N12 emerged as the most promising candidate for transporting FAV, showcasing notably moderate recovery time (ranging from 29.01 ms to 7.25 s at 298.15 K). Remarkably, the CuB11N12 system exhibited exceptional electronic sensitivity (ΔEgap = 65.38 %) to the FAV drug, surpassing other modified systems. Among the modified cases, the Cu-decorated Cu@b64 and Cu@b66 nanocages showed the most significant decrease in energy levels before and after FAV absorption, reducing from 3.28 eV and 3.33 eV to 1.54 eV and 1.59 eV, respectively. This elucidation may lay the foundation for developing effective drug-delivery systems using nanocages for targeted therapies. In conclusion, this study offers a comprehensive insight into the interaction mechanism between the FAV drug and B12N12, unveiling the potential of Cu-modified B12N12 nanocages as promising candidates for delivering the FAV drug.

Assessment of the quantum valence molecular machine for a rotaxanic complex

Rotaxanic type molecular machines are very intensively investigated because of their potential for the development of nanotechnology. We have applied the consecrated HSAB principle (“hard likes hard and soft likes soft”) to a small rotaxanes molecular series pH-switchable for determining which resulted interlocked system is more favorable to be further consider and functionalized as a molecular machine and also we have found the quantum structural models in inter-conversion dynamics in terms of frontier molecular orbitals and chemical reactivity. The obtained results strengthen the results obtained in previous studies.

Synthesis, DFT investigation, antioxidant, molecular docking and ADME-T properties of N′-(1-benzylpiperidin-4-ylidene) furan-2-carbohydrazide derivatives against SARS-CoV-2 spike proteins

ABSTRACT A novel synthetic reaction was used to produce a piperidine derivative, specifically N′-(1-benzylpiperidin-4-ylidene)furan-2-carbohydrazide (BPFC). The structure of the synthesised compound was confirmed through FT-IR, 1H-NMR and 13C-NMR spectral analysis. DFT calculations were performed to optimise structural parameters and investigate Natural Bond Orbital (NBO) analysis, Frontier Molecular Orbitals (FMOs), Molecular Electrostatic Potentials, Mulliken Charge Analysis, and Non-linear Optical properties. The predicted chemical shift values align well with the expected results. The antioxidant properties of the newly synthesised compound were assessed using DPPH, ABTS, and H2O2 radical scavenging assays. Molecular docking studies were also carried out to explore the binding mechanism of the compound with COVID-19-related proteins, particularly 6WCF and 6LU7. Additionally, the synthesised compound was assessed for drug-likeness and ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) properties, revealing favourable pharmacokinetic profiles without any signs of toxicity.

Optimizing non-fullerene acceptor molecules constituting fluorene core for enhanced performance in organic solar cells: a theoretical methodology.

Looking for novel outstanding performance materials suitable for organic solar cells, we constructed a range of non-fullerene acceptors (NFAs) evolved from the recently synthesized acceptor molecule identified as DICTIF, structured around fluorene core where 2-(2,3-dihydro-3-oxo-1H-inden-1-ylidene) propanedinitrile presented the terminals end-groups. Employing density functional theory (DFT) and time dependent-DFT (TD-DFT) simulations, we have simulated the impact of altering the end groups of DICTIF molecule by five assorted acceptors molecules, for the purpose of exploring their opto-electronic properties and their performance in organic solar cell (OSC) applications. We proved that the designed non-fullerene acceptors provide enhanced efficiency compared to the synthesized molecule, such as planar geometries and narrower energy gap ranging from 1.51 to 1.95 eV. A red shift in absorption was observed for all tailored molecules (λmax = 583.5-711.4 nm) as compared to the reference molecule (λmax = 578 nm).Various decisive factors such as frontier molecular orbitals (FMOs), exciton binding energy (EB), absorption maximum (λmax), open circuit voltage (VOC), reorganization energies (RE), transition density matrix (TDM), reduced density gradient (RDG), and electron-hole overlap have also been computed for analyzing the performance of NFAs. Low reorganizational energy values facilitate charge mobility which improves the conductivity of all the designed molecules. This study showed that our novel tailored molecules might be suitable candidates for the fabrication of highly efficient photovoltaic materials. After testing various hybrid functionals, optimized geometries were assigned using DFT HSEH1PBE/6-31G(d) level of theory. Electronic excitations and absorption spectra were investigated using the TD-DFT MPW1PW91/6-31G(d) level of theory. We ascertained that HSEH1PBE/6-31G(d) level of theory yield the closest calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of the DICTIF to the corresponding experimental ones and that TD-MPW1PW91//6-31G(d) was the most suitable level of theory for exploring electronic excitations and finding the maximum of absorption (λmax).

New Molecularly Flexible Self-Assembling Benzothiadiazole Derivatives: Mesomorphism And DFT Investigations

In the present study, we have synthesized symmetric/unsymmetrical BTD embedded self-assembling molecules and investigated for their mesomorphic properties. Two symmetrical series (BTDK-(2-18) and BTDC-(4-18)) comprises benzothiadiazole moiety as a central core unit which is connected to two different systematically varied end-groups, alkoxy ester and alkoxy coumaryl unit connected through ether and imine linkages. On the other hand, the asymmetric molecules have an alkoxy chalconyl unit at one end and a formyl group at the other. It was observed that, the mesomorphism is completely depends on the molecular flexibility. New molecules revealed mesomorphic behaviour with N (nematic), SmA (smectic-A) and SmC (smectic-C) mesophase with high thermal stability and greater range. Changes in mesogenic units (alkoxy ester & alkoxy coumaryl unit) and the impact of altering the alkoxy chain at both ends have been investigated. Interesting evaluation has been carried out on the molecular flexibility which resulted in different mesomorphic behaviour of molecules under study. Furthermore, the experimentally established values of the mesophase thermal stability (Tc) and mesophase temperature ranges (ΔTSmA, ΔTSmC, and ΔTN), as well as the type of the mesophase, were related to the calculated quantum chemical parameters (Frontier molecular orbitals (FMOs), Aspect Ratio, Polarizability, dipole moment, molecular and electrostatic potential (MEP)) that were obtained by using the DFT method of the investigated compounds.

Solvent-free mechanosynthesis of Schiff bases derived from thiadiazole with potential application in sensing ionic species and NLO applications

In this work, we report the solvent-free mechanosynthesis of three Schiff bases (SBs) derived from 1,3,4-thiadiazole covalently bonded to indole (Th-In), quinoline (Th-Qn) and triphenylamine (Th-TPA) groups. This green chemistry method showed a drastic reduction in reaction time and avoidance of solvents for obtaining SBs, with good reaction yields. The molecular structures of SBs were investigated by computational chemistry calculations, with global reactivity parameters indicative of electron acceptor behavior, estimation of frontier molecular orbitals, and their theoretical band gaps of 3.49 and 3.4 eV for Th-In and Th-Qn, respectively, and the lowest of 299 eV for Th-TPA. To evaluate the possible NLO response, the hyperpolarizabilities (β) were also estimated, which are several orders of magnitude higher than the urea value used as a reference. The absorption and emission spectra were calculated using TD-DFT. These results showed a larger redshift for Th-TPA, with possible charge transfer processes more intense than those obtained for Th-In and Th-Qn. The photophysical properties of the Schiff bases were determined, with band gap values for Th-In, Th-Qn, and Th-TPA of 2.53, 2.66, and 2.39 eV in solution and 2.77, 2.26, and 2.21 eV in film, respectively. When the SBs were evaluated as potential naked-eye colorimetric chemosensors, colorimetric changes were observed in Fe2+, Fe3+, Pb2+, Cu2+, and Ag+ ions, with Ag+ being the most promising. Z-scan was used to evaluate the nonlinear response of the SBs and showed saturable absorber behavior with self-focusing processes. Cyclic voltammetry was used to determine the electrochemical band gaps, which were 2.70, 2.71, and 1.98 eV for Th-In, Th-Qn, and Th-TPA, respectively. Th-TPA exhibits superior optical and electrical properties among the three SBs investigated. In addition, it exhibits photochromism, which can be used in conjunction with its other properties in NLO and sensor applications.

Investigating the antioxidant potential and mechanism of a hydrazide bioactive component of garlic: insights from density functional theory calculations, drug-likeness and molecular docking studies.

Glutathione remains one of the most efficient antioxidant compounds in living systems, and the biological abilities of hydrazides have been well documented in literature. This study highlights the phytochemical constituents of garlic and the separation of the bioactive benzoic acid, 4-chloro- 1-(4-methoxyphenyl) hydrazide (BA4C) using gas chromatography-mass spectroscopy (GC-MS) technique. Preliminary phytochemical screening reveals the presence of alkaloids, saponins, flavonoids, tannins, terpenoids, steroids and phenols. Computationally, compound BA4C was optimized using the B3LYP/aug-cc-PVDZ DFT method. Spectroscopic studies of the compound involved analysis of the vibrational FT-IR frequencies and the modes of vibrations. Frontier molecular orbitals analysis records an energy gap of 4.3391eV; NBO studies reveal that the compound has strong perturbation energies of 246kcal/mol and 269kcal/mol among its intramolecular interactions such as *C12 - C13 to *C14 - C15 and *C11 - C16 to *C14 - C15, respectively. According to the visualization of non-covalent interactions, steric repulsions were observed at the core of the phenyl and benzene rings. However, other regions of the compound depict a significant balance of forces between steric repulsions and van der Waals forces. To significantly deduce the reducing power of compound BA4C, electrons were found to be highly localized at the methoxy and hydrazide moieties significantly implying their propensity to donate electrons to oxidized systems. Furthermore, ADMET analysis reveals that the compound has two hydrogen donors. Most significantly, the compound binds to NADPH dehydrogenase (5V4P) and glutathione reductase (1XAN) with binding energies of - 6.0kcal/mol and - 8.0kcal/mol showing considerable favourable binding feasibility as well as forming plural hydrogen bonds with the amino acid residues. Notably, BA4C was bonded at the active site of 1XAN, which implies the ability of the compound for the reduction of oxidized glutathione.

Exploring the impact of heterocyclic bridges for tuning the amplitudes of Nonlinear optical properties under Gas, IEFPCM and COSMO solvent models

Nonlinear optical (NLO) materials are a distinctive class of materials due to their NLO response and wide range of applications. We present a systematic quantum chemical study for designing triphenylamine based derivatives (1Ph to 3PhDTDZ) by modifying central bridge with various size and types of heterocyclic rings. Density functional theory (DFT) method is used to calculate the NLO properties including linear and third-order NLO polarizabilities (α and γ) by using M06-2X functional coupled with the 6-311G** basis set. The calculation results predict that among the designed compounds, 1PhDTDZ has the highest third-order NLO polarizability of 2347.7 x 10−36 esu and lowest transition energy of 1.828 eV. On the other hand, 3PhDTDZ has a greater amplitude (108.5 x 10−24 esu) of static linear polarizability (αiso). We also computed frequency-dependent third-order NLO polarizability values at various laser wavelengths (1500 nm to 1970 nm). This provides valuable information about the complex interaction between light and matter. Dynamic second hyperpolarizability of electro-optic Pockels effect (EOPE effect, (γ (−ω; ω,0,0)) is calculated at 1500 nm laser wavelength with a larger γ-amplitude of 36708.4 x 10−36 esu. The effect of solvent on α and γ has also been the primary focus of this research. An extensive solvation impact has been studied using integral equation formalism Polarizable Continuum Model (IEFPCM) and Conductor-like Screening Model (COSMO). Magnitudes of αiso and 〈γ〉 have shown variation from gas to solvent methods. While among solvents, amplitudes are seen 3.87 % to 11.29 % greater under the effect of COSMO-methanol than PCM-methanol. The Frontier molecular orbital (FMO) studies found a significant decrease in energy band gaps from 5.75 eV to 2.98 eV. Since our systems exhibit remarkable photovoltaic properties, they can be used as dye-sensitized solar cells (DSSCs). Their open circuit voltage (VOC) ranging from 1 eV to 4 eV. Thus, our designed triphenylamine based derivatives with distinct central heterocyclic bridges showcase remarkable efficiency as NLO materials, with additional benefits of exhibiting good photovoltaic properties.

Comprehensive analysis of ferroelectric, piezoelectric, mechanical, and nonlinear optical properties of imidazolium d-camphorsulfonate single crystals

Single crystals of imidazolium d-camphorsulfonate (D-ImCS) are synthesized through the slow evaporation solution method. Powder X-ray diffraction reveals that the grown crystals have crystallized in the monoclinic phase with non-centrosymmetric space group P21. UV–visible spectroscopy measurements showed that D-ImCS crystals only absorb in the UV region. Photoluminescence studies indicated emissions in the blue and violet regions. The functional groups present in the crystal were identified through FTIR analysis. The soft nature of the crystal was identified using Vicker's microhardness testing. Dielectric analysis reveals the transition temperature Tc= 365.7 K. The piezoelectric charge constant (d22) is determined to be ±8 pC N−1. The polarization hysteresis loop demonstrates the ferroelectric nature. The presence of NLO property is demonstrated through SHG. Density Functional Theory (DFT) utilizing Gaussian 16 W software provided the optimized structure, UV–visible absorbance, FTIR spectra, frontier molecular orbitals, density of states, molecular electrostatic potential, atomic charge distribution, natural population analysis and non-linear optical properties (NLO). This computational approach complements and validates experimental findings, resulting in a thorough knowledge of D-ImCS behavior and properties.

A strategy for treatment of low-grade ore: Efficient separation and purification of iron

The gradual depletion of mineral resources has led to the emergence of a new engineering challenge in the field of mineral processing: the effective treatment of low-grade ores. In this study, the low-grade titanium ore leaching solution was employed as the raw material. The extraction ability of a series of hydroxyl extractants for the most common metal iron in minerals was investigated. As a result, a new high-quality processing system for low-grade ore with branched-chain octanol as the core component was constructed. In the treatment of mineral leaching solution, branched-chain octanol has high selectivity and large capacity (111.7 g/L) for iron. It was capable of efficiently removing a significant quantity of iron ions in low-grade ores that were not anticipated to be present. By employing quantum chemical (QC) methodologies, the mechanism for the high selectivity of branched-chain octanol for Fe(Ⅲ) has been elucidated by analyzing the frontier molecular orbital (FMO) energy of acid salts of common metals in minerals. Combined with spectral analysis and slope method, the structure of the extracted complex was confirmed to be [n-R8-OH]2·H·FeCl4. On the basis of system optimization, a three-stage countercurrent extraction and three-stage countercurrent stripping was employed to remove all the Fe(Ⅲ) in the mineral leaching solution. And after detecting, the purity of the obtained Fe(III) solution was greater than 99.5 %. In the treatment of low-grade minerals, especially those containing key metals, the branched-chain octanol extraction system demonstrates high selectivity and reliability, which is a effective means to improve the quality of mineral leaching solution.