Electron Density Distribution Function Research Articles

Preliminary Exploration of Low Frequency Low-Pressure Capacitively Coupled Ar-O2 Plasma

Non-thermal plasma as an emergent technology has received considerable attention for its wide range of applications in agriculture, material synthesis, and the biomedical field due to its low cost and portability. It has promising antimicrobial properties, making it a powerful tool for bacterial decontamination. However, traditional techniques for producing non-thermal plasma frequently rely on radiofrequency (RF) devices, despite their effectiveness, are intricate and expensive. This study focuses on generating Ar-O2 capacitively coupled plasma under vacuum conditions, utilizing a low-frequency alternating current (AC) power supply, to evaluate the system’s antimicrobial efficacy. A single Langmuir probe diagnostic was used to assess the key plasma parameters such as electron density (ne), electron temperature (Te), and electron energy distribution function (EEDF). Experimental results showed that ne increases (7 × 1015 m−3 to 1.5 × 1016 m−3) with a rise in pressure and AC power. Similarly, the EEDF modified into a bi-Maxwellian distribution with an increase in AC power, showing a higher population of low-energy electrons at higher power. Finally, the generated plasma was tested for antimicrobial treatment of Xanthomonas campestris pv. Vesicatoria. It is noted that the plasma generated by the AC power supply, at a pressure of 0.5 mbar and power of 400 W for 180 s, has 75% killing efficiency. This promising result highlights the capability of the suggested approach, which may be a budget-friendly and effective technique for eliminating microbes with promising applications in agriculture, biomedicine, and food processing.

The Effect of Ethanol on Lipid Nanoparticle Stabilization from a Molecular Dynamics Simulation Perspective.

Lipid nanoparticles (LNPs) have emerged as a promising delivery system, particularly for genetic therapies and vaccines. LNP formation requires a specific mixture of nucleic acid in a buffered solution and lipid components in ethanol. Ethanol acts as a lipid solvent, aiding the formation of the nanoparticle's core, but its presence can also affect LNP stability. In this study, we used molecular dynamics (MD) simulations to investigate the physicochemical effect of ethanol on LNPs and gain a dynamic understanding of its impact on the overall structure and stability of LNPs. Our results demonstrate that ethanol destabilizes LNP structure over time, indicated by increased root mean square deviation (RMSD) values. Changes in the solvent-accessible surface area (SASA), electron density, and radial distribution function (RDF) also suggest that ethanol affects LNP stability. Furthermore, our H-bond profile analysis shows that ethanol penetrates the LNP earlier than water. These findings emphasize the importance of immediate ethanol removal in lipid-based systems during LNP production to ensure stability.

Quantum Chemical Approach of Hexaammine (NH3)6 complexant with alkali and alkaline earth metals for their potential use as NLO materials

In this study, nine new electron rich compounds are presented, and their electronic, geometrical, and nonlinear optical (NLO) characteristics have been investigated by using the Density functional theory. The basic design principle of these compounds is placing alkaline earth metal (AEM) inside and alkali metal (AM) outside the hexaammine complexant. The properties of nine newly designed compounds are contrasted with the reference molecule (Hexaammine). The effect of this doping on Hexaamine complexant is explored by different analyses such as electron density distribution map (EDDM), frontier molecular orbitals (FMOs), density of states (DOS) absorption maximum (λmax), hyperpolarizabilities, dipole moment, transition density matrix (TDM). Non-covalent interaction (NCI) study assisted with isosurfaces has been accomplished to explore the vibrational frequencies and types of synergy. The doping of hexaammine complexant with AM and AEM significantly improved its characteristics by reducing values of HOMO-LUMO energy gaps from 10.7eV to 3.15eV compared to 10.7 eV of hexaammine. The polarizability and hyperpolarizability (αo and βo) values inquisitively increase from 72 to 919 au and 4.31 × 10−31 to 2.00 × 10−27esu respectively. The higher values of hyperpolarizability in comparison to hexaammine (taken as a reference molecule) are credited to the presence of additional electrons. The absorption profile of the newly designed molecules clearly illustrates that they are highly accompanied by higher λmax showing maximum absorbance in red and far-red regions ranging from 654.07 nm to 783.94 nm. These newly designed compounds have superior outcomes having effectiveness for using them as proficient NLO materials and have a gateway for advanced investigation of more stable and highly progressive NLO materials.

The Electronic Properties of Cadmium Naphthalene Diimide Coordination Complex.

The computational simulations for electronic properties of cadmium (Cd) coordinated L-alanine NDI ligand (H2-l-ala NDI) based complex are the focus of this research. For the first time, the Cd-NDI complex (monomer) has been produced using water as the solvent; this is a new approach to synthesizing the Cd-NDI complex that has not been reported yet. Along with crystallography and Hirsch field analysis, CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets were used, and in-depth characterisation of the Cd-NDI complex by following DFT and TD-DFT hypothetical simulations. Hyperpolarizabilities, frontier molecular orbitals (FMOs), the density of states (DOS), dipole moment (µ), electron density distribution map (EDDM), transition density matrix (TDM), molecular electrostatic potential (MEP), electron-hole analysis (EHA), and electrical conductivity (σ) have all been studied regarding the Cd-NDI complex. The vibrational frequencies and types of interaction are studied using infrared (IR) and non-covalent interaction (NCI) analysis with iso-surface. In comparison to the Cd-NDI complex with 2.61, 2.42 eV Eg (using CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets, respectively) and 376 nm λmax, (in case of B3LYP/LANL2MB λmax is higher), H2-l-ala NDI have 3.387 eV Eg and 375 nm λmax, metal-ligand coordination in complex dramatically altered charge transfer properties, such as narrowing band gap (Eg). Based on the electronic properties analysis of Cd-NDI complex, it is predicted that the Cd-NDI complex will have a spectacular (nonlinear optical) NLO response. The Cd-NDI complex is discovered to be advantageous for the creation of future nanoscale devices due to the harmony between the Cd metal and H2-l-ala NDI, in addition to their influences on NLO characteristics.

MIDDLE RANGE ORDER IN GLASSES OF La2O3–Nb2O5–B2O3 AND BaO–Nb2O5–P2O5 SYSTEMS ACCORDING TO X-RAY TOTAL SCATTERING

We have obtained the X-ray total scattering patterns at wavelength 0.20735 ? and corresponding to them radial distribution functions (RDF) of electron density for glasses in the La2O3–Nb2O5–B2O3 and BaO–Nb2O5–P2O5 systems. The RDF demonstrate separate peaks at distances below ~1 nm which points on the middle range ordering in the considered glasses. The consideration of RDF for BaO–Nb2O5–P2O5 glasses system with high concentration of BaO show that the middle range order is caused by the polyhedra chains of ideal BaO crystal, and these chains does not belong to any low-index crystal plane. For La2O3–Nb2O5–B2O3 glasses system the polyhedra chains are observed which resemble those in the LaB3O6 crystal, with polyhedra bound through borate groups. For all considered glasses the niobium polyhedra does not form extended chains.

Alkali and Transition Metal-Doped 15-Crown-5 with Enhanced Nonlinear Optical Response: A DFT Study

In this study, geometries, electronic structure and first hyperpolarizability of metals doped 15-crown-5 (C5M) were explored through the density functional theory (DFT) method. Alkali metals (Li, Na, K) and silver (Ag) were placed inside and outside of the crown ether, respectively, to deliver three compounds designated as Li[C5M]Ag, Na[C5M]Ag and K[C5M]Ag. All designed complexes were optimized at singlet, triplet, quintet and septet states, where the singlet state was identified as the stable state. The influence of doping on C5M can be investigated by energy gap fluctuation and it was noted that the smallest energy gap (4.68[Formula: see text]eV) was exhibited by K[C5M]Ag among all the intentional complexes, in contrast to reference C5M (12.73[Formula: see text]eV). Moreover, the density of state (DOS), transition density matrix (TDM), noncovalent interaction (NCI), molecular electrostatic potential (MESP) and electron density distribution map (EDDM) analysis were implemented. Static isotropic polarizability values were observed in the range of [Formula: see text]–[Formula: see text] esu which were comparable to dynamic isotropic polarizability values; [Formula: see text]–[Formula: see text]. Li[C5M]Ag revealed maximum first hyperpolarizability ([Formula: see text]) of [Formula: see text][Formula: see text]esu with the minimum transition energy ([Formula: see text]) of 2.93[Formula: see text]eV.

Description of non-covalent interactions in benzyl chalcocyanate crystals from smoothed Cromer–Mann electron density distribution functions

A well-known method to characterize non-covalent interactions consists in the topological analysis of electron density distribution (EDD) functions, complemented by the search for minima in the reduced density gradient (RDG) distributions. Here, we characterize intermolecular interactions occurring in crystals of benzyl chalcocyanate compounds through bond critical points (BCP) of the promolecular electron density (ED) built from the crystallographic Cromer–Mann parameters, at several smoothing levels t. The trajectories formed by the t-dependent BCP locations are interpreted in terms of the intermolecular interactions occurring within the crystal arrangements. Chalcogen…nitro BCPs are clearly present in the unsmoothed EDDs but are annihilated as t increases, while chalcogen…chalcogen BCPs appear and are among the only BCPs left at the highest smoothing level. The chalcogen bonds are differentiated from the other chalcogen interactions through the linear chalcogen…BCP…nitro geometry at low smoothing level and their more negative Laplacian values. The annihilation of CPs can be followed by the apparition of a RDG minimum, associated with a very weak interaction. Along the BCP trajectories, the Laplacian shows a progressive concentration of the ED in the intermolecular space within the crystals and adopts the most negative values at the shortest atom…atom separations. At the termination point of a BCP trajectory, the drastic increase of the ellipticity value illustrates the flattening of the EDD.

Experimental Spectroscopic, Quantum Chemical, Molecular Docking, and Molecular Dynamic Simulation Studies on Hydantoin (Monomer and Dimer)

The quantum chemical properties of hydantoin (imidazolidine-2,4-dione) have been studied by the DFT method (density functional theory) and experimentally by FT-IR, UV–Vis, 1H, and 13 C NMR. The B3LYP technique is used to determine HOMO-LUMO, vibrational frequency, and other parameters as well as to optimize the structure. Along with that vibrational mode assessment, the estimated vibrational frequencies were compared to experimental FT-IR spectra. MEP (molecular electrostatic potential) analysis and a Fukui function analysis were both done to look into the reactive regions of the molecule in order to look into the charge distribution of the molecule. Additionally, the electron localization function (ELF) value was examined to reveal details about the chemical composition, molecular bonding, and reactivity. The calculation of UV–visible spectra using the TD-DFT/PCM approach is done, and the results are contrasted with UV spectra that have been calculated experimentally. From HOMO to LUMO orbitals, electron excitation analysis was carried out. Hole and Electron density distribution (EDD and HDD) maps were created in an excited state using various solvents. The intermolecular interactions on the crystal surface were described and evaluated using fingerprint plots and Hirshfeld surface analyses. The Hirshfeld surface was used to identify different kinds of intermolecular interactions, including N–C, N–H, N–O, O–C, and O–H. The 1H-NMR and 13 C-NMR shifts were calculated using the GIAO method, and the results were compared to experimental spectra. In a biological investigation utilizing several receptors, molecular docking was employed to identify the most effective ligand-protein interactions. The stability of biomolecular systems was investigated using a molecular dynamics simulation.

Features of hydrogen reduction of SiF4 in ICP plasma

Probe diagnostics is used to determine the electron temperature and electron number density in a low pressure inductively coupled plasma (ICP) ignited in the mixture of SiF4, Ar and H2. Emission spectra of mixtures with different stoichiometry of components are investigated and the electron density distribution function (EDDF) is estimated. The optimal conditions for high conversion of SiF4 into Si are found by studying the dependence of the yield of silicon upon the ratio of reagents. The maximum achieved yield of silicon is 85% under the optimal conditions. Based on the analysis of IR and MS spectra of exhaust gases, 5% of initial SiF4 converts into volatile fluorosilanes. A rate of production of Si is 0.9 g/h at the energy consumption 0.56 kWh /g.

Optical Emission Spectroscopic Measurement of Argon Low-Pressure Inductively Coupled Plasma Based on the Optimization Algorithm of Plasma Diagnostic Model

Previously, we reported an optimization algorithm based on a plasma diagnostic model for optical emission spectroscopic (OES) measurements. In this study, we improved the algorithm. In the improved algorithm, the dependence of unimodality of reduced population density on electron temperature, electron density, and electron energy distribution function (EEDF) was discussed. Furthermore, electron temperature, electron density, and EEDF of 10 Pa argon inductively coupled plasma were diagnosed to experimentally evaluate the proposed algorithm. The diagnosis results were compared with those of the line-pair method and excitation temperature conversion method. The reduced population density distribution, which was calculated under the condition of the result of the proposed method, was in good agreement with the experimental result by OES measurement, thereby demonstrating the reliability of our proposed method.

Remarkable non-linear optical properties of gold cluster doped graphyne (GY): A DFT study

The nonlinear optical (NLO) properties of gold (Au) doped graphyne (GY) complexes are the subject of this quantum mechanical investigation. Detailed profiling of GY@Aucenter, GY@Auside, GY@2Auabove,GY@2Auperpendicular, and GY@3Aucenter is accomplished at CAM-B3LYP/LANL2DZ. The differential influence of various GY based complexes on molecular geometry, vertical ionization energy (VIE), interaction energy (Eint), frontier molecular orbitals (FMOs), density of states (DOS), absorption maximum (λmax), molecular electrostatic potential (MEP), electron density distribution map (EDDM), transition density matrix (TDM), dipole moment (μ) and non-linear optical (NLO) properties have been investigated. Non-covalent interaction (NCI) analysis has been done to explore the sort of interactions in designed complexes. The vibrational frequencies are probed via infrared (IR) analysis. Doping tactics in all complexes dramatically changed charge carrier properties, such as shrinking band gap (Eg) and increasing λmax in the range of 3.97–5.58 eV and 288–562 nm respectively, compared to pure GY with 5.78 eV Eg and 265 nm λmax. When compared to GY (αO = 281.54 andβO = 0.21 au), GY@3Aucenter exhibited a significant increase in static mean polarizability (αO = 415 au) and the mean first hyperpolarizability (βo = 3652 au) attributable to its lowest excitation energy (ΔE). GY doping has been discovered to be advantageous for designing potential nanoscale devices by focusing on the symphony between small Au clusters and GY and their impacts on NLO aspects.

Experimental Spectroscopic, Quantum Computational, Hirshfeld Surface, Molecular Docking, and Electronic Excitation Studies on an Antibiotic Agent: SDZ

In this report sulfadiazine (SDZ) has been experimentally and quantum chemically investigated. Computational analysis was carried out theoretically using the density functional theory (DFT) approach/B3LYP and 6-311++G(d,p) level to obtain optimized geometrical structure and vibrational modes analysis and other various calculations. A detailed description of the intermolecular interactions of the crystal surface were carried out by means of Hirshfeld surface analysis and fingerprint plots. Exploration of electron excitation from occupied to unoccupied orbitals in a single electron pair occurs, with dimethyl sulfoxide (DMSO) and MeOH as solvents and electron density distribution (EDD) and hole density distribution (HDD) maps were drawn in an excited state. The molecule reactivity region MEP, molecular stability, natural bond orbital (NBO), HOMO–LUMO, dipole moment (μ), polarizability (α), and hyperpolarizability (β) nonlinear optical (NLO), have all been taken into account. NBO analysis was carried out and the hybridization of atoms that form bonds was evaluated. The charge transfer of the title molecule has been examined by TD-DFT method The UV–Vis spectrum was obtained by employing the TDDFT/PCM method and compared with experimental spectra. Calculated HOMO→LUMO energy gap and charge transfer in the molecule was investigated. Chemical descriptors indicate the reactivity of the molecule as a whole, and Fukui function calculations were used to examine the reactive locations of the compound. The electrophilicity index was calculated and the bio-activity of the molecule was studied. However, biological research like drug-likeness and molecular docking are also done on the molecule.

Molecular hydrogen sorption capacity of P216-schwarzite: PM6-D3, MP2 and QTAIM approaches

Schwarzites, due to their high porosity, are among prospective materials for the sorption of different gases, including hydrogen. Their surface possesses negative Gaussian curvature that intimately determines how many carbon atoms each hydrogen molecule will interact with, which, in turn, defines the fraction of hydrogen that would be sorbed in the schwarzite. The critical question about contributions to the sorption of the surface topology and electronic effects is solved here. Within the framework of the QTAIM theory, the topological parameters of the electron density distribution function at the bond critical points characterizing the dispersion interaction of the H2 molecule with the carbon surface are estimated. On the example of molecules [6]circulene and [7]circulene, it was shown that, despite the electronic effects arising from the bending of this surface, on average, the energy of physical sorption of hydrogen obtained using MP2 calculations changes insignificantly – by about 0.1 kJ/mol in the case of, for example, vertical orientation of the molecule. By calculating the thermochemical properties by the PM6-D3 method, the dependence of the weight fraction of hydrogen sorbed in P216-schwarzite on the external gas pressure and the temperature has been established. In particular, it was shown that at 300 K and 10 MPa, this value is 4.6%, slightly higher than other carbon nanostructures with similar density, porosity, and accessible surface area values.

Experimental, theoretical, hirschfeld surface, electronic excitation and molecular docking studies on fomepizole(4-Methyl-1H-pyrazole)

4-Methylpyrazole (4-MP) with the trade name Fomepizole studied Experimentally and theoretically. Theoretical calculations carried out by Density Functional Theory (DFT) with basis set 6–311++G(d,p). 3D and 2D surface analysis was carried by Hirshfeld surface analysis. The B3LYP method and the 6–311++G(d,p) basis set were used to optimize the molecular structure and vibrational modes. VEDA (Vibrational Energy Distribution analysis) successfully carried out and complete tasks for the distribution of potential energy. Binding energies, elliptically and isosurface projection determined by Atom in molecule theory (AIM) and bioactivity of the titled molecule was analyzed. The HOMO-LUMO mapping are reported and chemical activity in the molecule was determined. Chemically active sites of the molecule were also defined by Molecular electrostatic potential (MEP) and Fukui Function. The TDDFT method and the PCM solvent model were used for the analysis of electronic properties such as UV–Vis (in the gas phase, methanol and DMSO) and compared with the experimental UV–Vis spectra. Electron excitation analysis from occupied to unoccupied orbitals in a single pair of electrons takes place. Hole and Electron density distribution maps (EDD and HDD) were drawn in an excited state with solvents. Intermolecular charge transfer (ICT) was explained with the help of Natural Bond Order (NBO). Study of donor-acceptor interconnections were done via NBO analysis. Exploration of intermolecular interactions via Hirshfeld surface showed 4-MP stabilized mainly by formation of C—H/H—C contacts. Drug-likeness and molecular docking was done to determine the nature and interaction between ligand and protein respectively by considering the further its uses in medicines.

Exploration of experimental, theoretical, Hirshfeld surface, molecular docking and electronic excitation studies of Menadione: A potent anti-cancer agent

In this report, experimental, Computational analysis of menadione (2 methyl-1,4 nathoquinone) has been carried out theoretically by (DFT) density functional theory using B3LYP method with 6-311++G (d,p) basis set. Vibrational spectroscopic study and various other parameters have been accomplished. AIM theory (Atoms in molecules) is used to calculate the ellipticity, iso-surface projection by electron localization function, and binding energies. The computational theoretical spectra of FT-IR showed great agreement with the experimental results. A detailed description of crystal surface intermolecular interactions was carried out and Hirshfeld surface analysis, fingerprint plots were drawn via crystal explorer software. The NBO study helped in analyzing the donor and acceptor interaction. The nucleophilic and electrophilic interactions of the molecule were determined by the Fukui function and Molecular Electrostatic Potential (MEP). TD-DFT with PCM model was done with different solvents. Exploration of electron excitation from occupied to unoccupied orbitals in a single pair of electrons takes place. With DMSO and MeOH as solvents, hole and electron density distribution maps (EDD and HDD) were drawn in an excited state. The HOMO → LUMO energy gap showed the strength and stability of the molecule. With the help of the electrophilicity index and other parameters, the biological potency of the molecule is theoretically estimated. The drug-likeness was also studied and molecular docking was done using different proteins and with binding energy −9.5, −8.3, and −6.2. The biomolecular stability was investigated using a molecular dynamics simulation.

Synthesis, Characterization, Crystal Structure, Hirshfeld Surface, Electronic Excitation, Molecular Docking, and DFT Studies on 2-Amino Thiophene Derivative

Ethyl-2-amino-5,6,7,8-tetrahydro-4H-cyclo-hepta[b]thiophene-3-carboxylate (EACHT) has been synthesized, characterized via single-crystal X-ray diffraction at 293 K and investigated quantum chemically by DFT approach, surface analysis by Hirshfeld and spectrochemically by NMR (1H-NMR and 13C-NMR), FTIR, and UV–Visible. The compound crystallizes in monoclinic crystal system with P21/c space group with Z = 4, with following unit cell dimensions: a = 9.5956 (3) Å, b = 9.5607 (4) Å, c = 13.7226 (7) Å. To get the optimized structure which is base for all the other calculations (vibrational frequency, NBO, natural hybrid orbital, nonlinear optical, frontier molecular orbital, etc.), B3LYP method with 6-311++G(d,p) basis set was used. Complete potential energy distribution assignments were done successfully by VEDA. 1H-NMR and 13C-NMR shifts were estimated by GIAO method and results were compared with experimental spectra. TDDFT method and PCM solvent model was utilized for electronic property analysis such as UV–Vis (in gas phase, ethanol, and DMSO) and compared with the experimental UV–Vis spectra. The HOMO and LUMO energy results emphasize adequate charge transfer was happened within the molecule. NBO analysis MEP surface analysis electron localization function Diagram and Fukui function analysis were done. Hole and Electron density distribution maps were drawn in two different excited states of higher oscillatory strength with DMSO, MeOH as solvents. Docking with seven different receptors, and drug likeness was also carried out.

Silver cluster doped graphyne (GY) with outstanding non-linear optical properties.

This research study addresses the computational simulations of optical and nonlinear optical (NLO) characteristics of silver (Ag) cluster doped graphyne (GY) complexes. By precisely following DFT and TD-DFT hypothetical computations, in-depth characterization of GY@Agcenter, GY@Agside, GY@2Agperpendicular, GY@2Agabove, and GY@3Agcenter is accomplished using CAM-B3LYP/LANL2DZ while the CAM-B3LYP/mixed basis set is used for study of 2GY@Agcenter, 2GY@Agside, 2GY@2Agperpendicular, 2GY@2Agabove, and 2GY@3Agcenter. The effects of various graphyne surface based complexes on hyperpolarizabilities, frontier molecular orbitals (FMOs), density of states (DOS), absorption maximum (λmax), binding energy (Eb), dipole moment (μ), electron density distribution map (EDDM), transition density matrix (TDM), electrostatic potential (ESP), vertical ionization energy (EVI) and electrical conductivity (σ) have been investigated. Infrared (IR), non-covalent interaction (NCI) analysis accompanied by isosurface are performed to study the vibrational frequencies and type of interaction. Doping strategies in all complexes impressively reformed charge transfer characteristics such as narrowing band gap (Eg) in the range of 2.58–4.73 eV and enhanced λmax lying in the range of 368–536 nm as compared to pure GY with 5.78 eV Eg and 265 nm λmax for (GY@Agcenter–GY@3Agcenter). In the case of (2GY@Agcenter–2GY@3Agcenter), when compared to 2GY with 5.58 eV Eg and 275 nm absorption, maximum doping techniques have more effectively modified λmax in the region of 400–548 nm and Eg, which is in the order of 2.55–4.62 eV. GY@3Agcenter and 2GY@3Agcenter reflected a noteworthy increment in linear polarizability αO (436.90 au) and (586 au) and the first hyperpolarizability βO (5048.77 au) and (17 270 au) because of their lowest excitation energy (ΔE) when studied in comparison with GY (αO = 281.54 and βO = 0.21 au) and 2GY surface (αO = 416 and βO = 0.06 au). Focusing on harmony between the tiny Ag clusters and graphyne surface as well as their influences on NLO properties, graphyne doping using its two-unit cells (2GY) is found to be expedient for the development of future nanoscale devices.

Synthesis, antibacterial, antifungal and computational study of (E)-4-(3-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-3-oxoprop-1-en-1-yl)benzonitrile

In the present work, synthesis, antibacterial, antifungal and computational study of synthesized (E)-4-(3-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-3-oxoprop-1-en-1-yl)benzonitrile (DHDOBN) chalcone derivative were explored. The computational study of the DHDOBN was performed using density functional theory (DFT) with B3LYP functional and 6-31G(d,p) basis set combination. Theoretical investigations about UV–vis and FT-IR spectral investigation of the DHDOBN was reported using TD-DFT/B3LYP/6-31G(d,p) and B3LYP/6-31G(d,p) levels, respectively. The computed UV–vis and FT-IR absorption spectral properties accord well with the outcomes of the experiments. The formation of the charge separation state as a result of the successful migration of electrons from the donor to acceptor unit through the π-bridge was confirmed by the analysis of electronic properties, including the frontier molecular orbitals (FMOs) analysis, molecular electrostatic surface potential (MESP), hole density distribution (HDD), and electron density distribution (EDD) map. highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LUMO) energy values were used to compute the ionisation potential, electron affinity, electronegativity, chemical hardness and softness, global electrophilicity, and chemical potential of the titled compound. The examined compound's significant DFT features were compared with those of other compounds that have been previously reported. In compound DHDOBN strong electron-withdrawing –CN group present at the para position makes the titled compound kinetically more reactive. The small EHOMO and ELUMO energy gap due to cyano group makes it soft and more polarizable molecule. The DHDOBN compound was tested for antibacterial activity against two Gram-negative bacterial strains namely E. coli and P. Vulgaris and two Gram-positive bacterial strains namely S. aureus and B. subtilis, whereas fungal inhibitory action was tested against A. Niger and C. albicans. The DHDOBN compound was revealed to show moderate antibacterial and antifungal potential.

Quantum chemical, spectroscopic, hirshfeld surface and molecular docking studies on 2-aminobenzothiazole

The quantum chemical properties and experimental spectroscopy of 2-aminobenzothiazole (2-ABT) were explored. DFT(Density functional theory) technique used to calculate different properties of 2-ABTcomputationally. Surface analysis carried out by Hirshfeld, and experimental spectrochemical analysis such as-NMR (1H NMR and 13C NMR), FT-IR, and UV-Visible examined experimentally. The B3LYP method with 6–311++G(d,p) basis set was used to obtain the optimal structure that serves as the foundation for all other calculations (vibrational frequency, NBO, NHO, NLO, FMO, and so on). Hirshfeld surface analysis and finger print plots were used to describe the intermolecular interactions on the crystal surface in detail. 2-ABT is stabilized primarily via the creation of H…H/C…H and S…H contacts, according to a Hirshfeld surface analysis of intermolecular interactions. VEDA completed all potential energy distribution assignments. The electron localization function was used to determine binding energy, ellipticity, and isosurface projection using the atom in molecule theory (AIM). The NBO analysis was used to determine the interactions between the donor and the acceptor. The molecule's reactive areas were revealed using Fukui functions and molecular electrostatic potential (MEP). UV–Vis spectrum calculated with different solvents using TD-DFT/IEFPCM techniques. ORCA calculated thermodynamic parameters such as free energy, enthalpy, and entropy at various temperatures. In the excited state, maps of hole and electron density distribution were generated using DMSO and MeOH. The bio-active probability of the chemical was theoretically proven by computing the electrophilicity index. Molecular docking is used to calculate and confirm protein-ligand interactions. The title molecule was also used in medicinal fields and for drug development.

Computational, spectroscopic, Hirshfeld surface, electronic state and molecular docking studies on phthalic anhydride

Phthalic anhydride (PA) was studied Spectroscopically by NMR (1H NMR and 13C NMR), FT-IR, UV-Visible and quantum chemically by DFT approach.3D and 2D surface analysis was carried by Hirshfeld surface. B3LYP method and 6-311++G(d,p) basis set were employed for optimization of molecular structure and for calculation of wave numbers of normal modes of vibrations. Detailed description of intermolecular interactions of crystal surface was done by 3D Hirshfeld surface analysis and 2D finger print plots. Hirshfeld surface also helps to explore intermolecular interactions in PA crystal. Hole and Electron density distribution maps were drawn in 2 different excited states of higher oscillatory strength with DMSO, MeOH as solvents. Structure was optimized and optimized bond lengths and angles were compared with the experimental bond lengths and Bond angle Parameters, were found in good agreement with each other. Complete potential energy distribution assignments were done successfully by VEDA. 1H NMR and 13C NMR shifts were estimated by GIAO method and results were compared with experimental spectra. TDDFT method and PCM solvent model was utilized for electronic property analysis such as UV–Vis (in gas phase, ethanol and DMSO) and compared with the experimental UV–Vis spectra. The HOMO/LUMO energy results emphasize adequate charge transfer is happened within the molecule. Study of donor-acceptor interconnections were done via NBO analysis. MEP surface analysis was done to demonstrate charge distribution in molecule. The degree of relative localization of electrons was analyzed via FLF Diagram. The Fukui function analysis give information regarding possible sites for attacks by different substituents. Molecular electrostatic potential (MEP) surface was drawn for analysis of reactive sites via 3-D colour representation. The biological study such as molecular docking was done with 6 different receptors to find the best ligand protein interactions and drug likeness was also carried out and found drug like character.