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An Fe(III)-carbonato six-coordinate picket fence porphyrin complex with the formula [K(2,2,2-crypt)][FeIII(TpivPP)(CO3)]·C6H5Cl·3H2O (I) has been synthesized and characterized by UV-Vis and FT-IR spectra. The structure of (carbonato)(α,α,α,α-tetrakis(o-pivalamidophenyl)porphinato)ferrate(III) was also established by XRD. The iron atom is hexa-coordinated by the four nitrogen atoms of the pyrrol rings and the two oxygen atoms of the CO32− group. Complex I, characterized as a ferric high-spin complex (S = 5/2), presented higher Fe-Np (2.105(6) Å) and Fe-PC (0.654(2) Å) distances. Both X-ray molecular structure and Hirshfeld surface analysis results show that the crystal packing of I is made by C-H⋯O and C-H⋯Cg weak intermolecular hydrogen interactions involving neighboring [FeIII(TpivPP)(CO3)]− ion complexes. Computational studies were carried out at DFT/B3LYP-D3/LanL2DZ to investigate the HOMO and LUMO molecular frontier orbitals and the reactivity within the studied compound. The stability of compound I was investigated by analyzing both intra- and inter-molecular interactions using the 2D and 3DHirshfeld surface (HS) analyses. Additionally, the frontier molecular orbital (FMO) calculations and the molecular electronic potential (MEP) analyses were conducted to determine the electron localizations, electrophilic, and nucleophilic regions, as well as charge transfer (ECT) within the studied system. [ABSTRACT FROM AUTHOR]

Anthraquinone derivatives are well recognized for their anticancer activities and pharmacological properties. In the present study, comprehensive theoretical and experimental FT-IR, FT-Raman, and UV-visible spectroscopic studies on the 1-Chloroanthraquinone (CAQ) molecule were carried out. The optimized molecular structure and harmonic vibrational frequencies was calculated using Gaussian 09 program. The experimental and calculated vibrational wavenumbers were assigned, which correlated well with the previous literature. The UV-visible absorption spectrum of the CAQ molecule was computed in the liquid phase (ethanol), which exhibits n–π* electronic transition, and the results were compared with the observed UV-visible spectrum. From the frontier molecular orbital analysis, the calculated energy gap value (4.03 eV) indicates that the CAQ molecule has a stable structure and the value was comparable with the band gap energy value of the reported bioactive molecules. The electron back donation from the carbonyl group oxygen atom to the benzene ring was identified using Mulliken atomic charge distribution analysis. Molecular electrostatic potential surface analysis confirms the reactive sites of the molecule. The natural bond orbital analysis validates electron back donation from the carbonyl group oxygen atom to the benzene ring of the CAQ molecule. The molecular docking analysis results that the CAQ molecule acts as a good inhibitor of histone deacetylase 6 (HDAC6) protein. HDAC6 protein is associated with oral squamous cell carcinoma. Thus, the present study paves the way for designing novel drugs for the treatment of oral squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

Several factors, including environment, behaviours, and heredity, influence the development of hypertension. The title compound dopamine D1 receptor agonist named (4S)-4-(3,4-dihydroxyphenyl)-1,2,3,4-tetrahydroisoquinoline-7,8-diol (4S4D4T) is one of the most important neurotransmitters associated with numerous neural disorders. Using DFT and quantum chemical simulations, the vibrational, electrical, and structural possessions of the heading compound were predicted. To carry out the quantum computational investigations, a highly compatible method entitled B3LYP basis set was adopted. Vibrational Modes of functional groups with PED values were calculated using VEDA software to compute geometric dimensions and assign fundamental vibrations. Using gas and solvent phases, MEP differentiates between nucleophilic and electrophilic sites and creates distribution for the charge of the molecules. The observed wavelength with (TDSCF) UV–Vis spectra for the various solvents phases were compared. The NBO approach provides an understanding of the electron delocalization that results from hyperconjugation. FUKUI analysis is used to determine the area of site reaction. Electron density's topological analysis was carried out using the QTAIM theory. The ADME (Absorption, Distribution, Metabolism, Excretion) profiles are produced with the Swiss ADME online tool. In summary, this dissertation offers a thorough examination that evaluates the impact of particular pharmaceuticals on solvation and enzyme efficiency using a combination of spectral and quantitative computing methodologies. Therefore, plans for further research can profit immensely by the information gathered. The results of protein-ligand docking using the Auto Dock method with various proteins suggest that the molecule has pharmaceutical properties against receptors.

An addition of carbon nanostructures to cement paste is problematic due to the difficulties in obtaining homogenous mixtures. The paper reports on a more effective way of mixing carboxylated multi-walled carbon nanotubes (MWCNT-COOH) in cement pastes. The additional biological impact of the studied nanomodified cement was analyzed in the case of two moss species’ vitality. The applied approach of obtaining a homogeneous mixture is based on intense mechanochemical mixing of MWCNT-COOH together with polycarboxylate superplasticizer (SP). As a result, a more homogenous suspension of MWCNT-COOH within a liquid superplasticizer, suitable for addition to hydrophilic cement paste, was obtained. FT-IR/Raman spectroscopy was used for materials’ characterization. To explain the mixing process at the molecular level, systematic theoretical studies using density functional theory (DFT) were performed. The structures, interaction energies and IR/Raman vibrational spectra of model carboxylic acids, mixed with functionalized SWCNTs as simplified models of real MWCNTs, were obtained. Due to the controversial opinions on the environmental hazards of carbon nanostructures, additional in vivo studies were performed. In this case, effects of cement modified by the addition of small amounts of MWCNT-COOH with SP in comparison to the composite without carbon nanostructures and control subsoil on the vitality of mosses Polytrichum formosum and Pseudoscleropodium purum were studied.

In this study, the geometry of BPHB (4-buthoxyphenyl 4'-hexylbenzoate), a thermotropic nematic liquid crystal with uniaxial molecular symmetry, was optimized and spectral analyses were performed. Gaussian09 software package and GaussView 5.0 graphical interface software programs were used for this purpose. Calculations were performed by Hartree-Fock HF/6- 31G(d,p) and density functional theory DFT/B3LYP/6-31G(d,p) methods. Molecular and thermodynamic structural parameters (electronic properties, electron affinity, electronegativity, molecular hardness and softness, electrophilic index, chemical potential), molecular charge distribution (Mulliken atomic charges), FT-IR spectra, molecular electrostatic potential map (MEP), HOMO-LUMO energies, dipole moments, total energies and electronic structure parameters of the optimized structure were calculated. The calculated values for both methods were compared and analyzed. [ABSTRACT FROM AUTHOR]

An Fe(III)-carbonato six-coordinate picket fence porphyrin complex with the formula [K(2,2,2-crypt)][FeIII(TpivPP)(CO3)]·C6H5Cl·3H2O (I) has been synthesized and characterized by UV-Vis and FT-IR spectra. The structure of (carbonato)(α,α,α,α-tetrakis(o-pivalamidophenyl)porphinato)ferrate(III) was also established by XRD. The iron atom is hexa-coordinated by the four nitrogen atoms of the pyrrol rings and the two oxygen atoms of the CO32− group. Complex I, characterized as a ferric high-spin complex (S = 5/2), presented higher Fe-Np (2.105(6) Å) and Fe-PC (0.654(2) Å) distances. Both X-ray molecular structure and Hirshfeld surface analysis results show that the crystal packing of I is made by C-H⋯O and C-H⋯Cg weak intermolecular hydrogen interactions involving neighboring [FeIII(TpivPP)(CO3)]− ion complexes. Computational studies were carried out at DFT/B3LYP-D3/LanL2DZ to investigate the HOMO and LUMO molecular frontier orbitals and the reactivity within the studied compound. The stability of compound I was investigated by analyzing both intra- and inter-molecular interactions using the 2D and 3DHirshfeld surface (HS) analyses. Additionally, the frontier molecular orbital (FMO) calculations and the molecular electronic potential (MEP) analyses were conducted to determine the electron localizations, electrophilic, and nucleophilic regions, as well as charge transfer (ECT) within the studied system.

Amodiaquine (AQ) was synthesized by a condensation reaction and characterized by experimental FT-IR, 1H and 13C nuclear magnetic resonance (NMR) and UV spectroscopies. In the present work, Density Functional Theory (DFT) calculations.The structural and spectroscopic (FT-IR, 1H and 13C NMR and UV) data of amodiaquine molecule in ground state have been investigated by using Density Functional Theory (DFT). The calculations have been performed at the using B3LYP method with 6–311++G(d,p) and 6–311++G(2d, p) basis sets theory level were performed, first, to confirm its structure, then to explain its reactive nature through its molecular properties such as natural charges, local and global reactivity descriptors or natural bond orbital (NBO). Afterwards, the calculated properties were compared with experimental results. The 1H and 13C NMR chemical shifts were calculated by using the gauge-independent atomic orbital (GIAO) method, while the electronic UV–Vis spectrum is predicted using the time-dependent density functional theory (TD-DFT). Globally, the computerized results showed good agreement close similarity with the experimental values. The molecular properties such as natural charges, local and global reactivity descriptors, molecular electrostatic potential (MEP), natural bond orbital (NBO) of title molecule were calculated insights into the stability, reactivity and reactive sites on the molecule.The calculated energy band gap (ELUMO-EHOMO) value of AQ was found to be 4.09 eV suggesting that it could be considered as a hard molecule with high stability, supported by global reactivity descriptors. Molecular electrostatic potential (MEP) analysis revealed heteroatoms (oxygen and nitrogen) as the most putative nucleophilic sites when hydrogen atoms to which they are linked appear as electrophilic sites. The potential use of amodiaquine as non-linear optical (NLO) material and its thermodynamic indicators have also been assessed.

In this work, characterization by 1H & 13C together with UV-Vis & IR spectroscopy has been accomplished for p-toluenesulfonic acid (p-TSA). The structural, electronic and vibrational properties of the heading compound were foretold using quantum chemical calculations through DFT. All the calculated data were compared with the experimental and found to be consisting with them. The comparison of computed data with experimental have been shown in terms of RMSD values (in case of IR, 1H and 13C NMR). The B3LYP functional with source set 6-311++G(d,p) was utilized to optimize the geometry of the compound, p-TSA. IR spectrum measurements have been made between 4000 - 400 cm−1. To calculate geometric dimensions, energies & wavenumbers, as well as to assign fundamental vibrations, the vibrational modes with the PED assignments were utilized. In solvents namely, MeOH and DMSO, the spectra of UV-Vis of the caption compound were captured between 200 and 400 nm.TD-DFT computations were used to ascertain the HOMO – LUMO energy gap & electronic transitions, which also replicate the UV-Vis absorption spectra. Hirsfeld Surface Analysis (HF) was also evaluated to determine the crystal structure's interactions. The electrophilic and nucleophilic locations were identified using the MEP. Furthermore, to study the biologic functions of p-TSA and to assess the optimum interactions of ligand – protein and similarity to the energetic ingredient, molecular docking was carried out.

AB S T R A C T: The Methyl Linoleate, also called polyunsaturated fatty acid, is a natural drug synthesis from 100% medicinal plant of L.AegleMarmelos. The title molecules structure conformed through GC-MS results. The geometry structure parameters on the title molecule were optimized and determinate at the same level of B3LYP/6-311++G (d,p) correlated with the XRD database. Thermodynamic properties estimated at different temperatures and the NBO used to analysis inter-intra molecular interaction, the first-order hyperpolarizability were also completed. The DFT were computed NMR, energy gap reported 5.33 eV it is related to biological activity and MEP used to predict the chemical reactive site of electrophilic and nucleophilic attack. The TD-DFT executed UV-Visible spectra found at 266 nm is good agreements with experimental value and the FT-IR spectra of each vibrational mode compared with the theoretical spectra and potential energy distribution PED% carried out. The PES studies have been estimated to investigate the configuration analysis of double bond. The molecular docking found the stability of protein-ligand complex on 4HOE receptor against candida diagnosis.

On Glycine Methyl Ester Hydrochloride (GMEHCl), X-ray crystallographic (Lattice parameter), FT-IR, FT-Raman, DFT, HOMO-LUMO, MEP, ADMET, and molecular docking investigations are studied. The small molecule (GMEHCl) docking analysis with the target protein revealed that this is a good molecule that docks well with a target connected to the Human estrogen receptor macromolecule. The improvement of electrostatic interactions between the protein and the ligand is made possible by molecular electrostatic potential (MEP). DFT-B3LYP calculations using the 6–31++G (d,p) basis set are used to determine the optimized geometry of the GMEHCl molecule, and the computed vibrational frequencies are assessed by comparing them to experimental results. Using a 2D fingerprint plot and Hirshfeld Surfaces, the molecular surface and hydrogen bonding interactions in the GMEHCl crystal structure were discovered and investigated. The parameters of absorption, distribution, metabolism, and excretion (ADME) were measured using the internet server preADMET.

The FT-IR and FT-Raman spectra was recorded within the range of 4000 -500 cm−1 and compared with the theoretically obtained spectra. The 13C and 1H NMR chemical shifts have been calculated using the GIAO technique, and the output has been compared with experimental data. The optimized molecular structure and stability analysis of the aztreonam compound have been calculated by the DFT/B3LYP/6–311++G(d,p) level of theory. The molecular electrostatic potential, chemical descriptors, and HOMO-LUMO energies were also calculated. The in silico pharmacological evaluation shows that the title molecule exhibit drug-likeness, and ADMET properties. The ADMET results also indicate that the molecule can be employed in anti-tuberculosis treatments to discover new drugs. Furthermore, molecular docking analyses have been performed to understand the most active binding sites of the compound with the target protein. The molecules are docked with the PknB protein, with free binding energy values of Aztreonam is -7.25 and Mitoxantrone is -6.79 kcal/mol.

Abstract The detailed theoretical and experimental (FT-IR, FT-Raman, UV-visible) spectroscopy analyses of the Ethyl Coumarin-3-Carboxylate (ECC) molecule were carried out. The ECC compound’s pharmacological properties were also investigated, utilizing antibacterial and anticancer activity investigations. Initially, the ECC molecule was optimized by the density functional theory B3LYP method with a 6-311 G++ (d,p) basis set using the Gaussian 09 W program. The optimized molecular structure provides the harmonic vibrational frequencies of the ECC molecule. The observed and computed vibrational wavenumbers were assigned and found to be well correlated. UV-Vis absorption spectrum analysis indicates that the molecule contains π →π* and n → π* electronic transitions. The Frontier molecular orbital analysis confirmed the molecular reactivity and bioactivity of ECC, while the Mulliken atomic charge distribution analysis pinpointed the molecule’s reactive sites. Antibacterial testing demonstrated the ECC compound’s inhibitory effect on various bacterial strains, with a particular impact on Klebsiella pneumonia. In vitro, anticancer assessments showcased ECC's stronger inhibitory effects on A549 lung cancer cell lines compared to HeLa cervical cancer cell lines. Additionally, in silico molecular docking investigations provided further validation that the ECC compound can inhibit the function of the epidermal growth factor receptor, a factor associated with lung cancer. As a result, this study lays the foundation for the development of novel drugs for lung cancer treatment. [ABSTRACT FROM AUTHOR]

The special properties of organic compounds are due to the polyvalence of the carbon atom. In this research, the organic single crystal of N-(4-acetyl −5-(4-(nitro) phenyl) −4,5-dihydro-1,3,4-thiadiazol-2-yl) -N-phenylacetamide (NTDZ) was successfully synthesized and crystallized in isopropanol by using slow evaporation solution growth method. FT-IR, 1H and 13C NMR spectroscopic techniques were used to characterize the presence of various functional groups in the NTDZ molecular structure. Single crystal X-ray data have been collected and used for the structural determination of NTDZ. The title crystal crystallized in the monoclinic space group P21/c, according to X-ray analysis. Besides, quantum chemical studies were carried out using the density functional theory calculation method. The theoretical and experimental geometrical parameters were compared indicating a good accordance between them. Moreover, surface shapes were displayed using 3D-Hirshfeld surface analysis, and 2D-fingerprint graphs were used to quantify the contributions of C–H...O and C–H...N intermolecular interactions. Furthermore, the vibration spectrum of the NTDZ is calculated and compared with that obtained by FT-IR spectroscopy, and the predicted vibration assignments are made according to the potential energy distribution (PED). The chemical shifts of 1H and 13C-NMR were calculated using the GIAO approximation and compared to experimental values. Using the TD-DFT method, the theoretical UV-Vis absorption spectrum was calculated in chloroform solvent to obtain the most important electronic transitions. Frontier molecular orbitals (HOMO and LUMO) indicate the charge transfer within the molecule. The global chemical reactivity descriptors (GCRD) were calculated. In addition, the MEP was also computed showing the functional groups responsible for building interactions with other molecules. Finally, the nonlinear optical behavior was investigated by the determination of the dipole moment (μ), the polarizability (α), and the first and second hyperpolarizabilities using the same level of theory. All of these findings suggest that the NTDZ crystal may be a viable candidate for NLO applications. New 1,3,4-thiadiazol derivative was synthesized. X-ray geometry was determined and confirmed by theoretical calculation. Electronic behavior was investigated by DFT and TD-DFT. NLO properties of the compound were also computed. [ABSTRACT FROM AUTHOR]

The newly synthesized 3-(2-Hydroxyphenyl)-1-phenyl propenone was analyzed. In this work, optimization of the 3-(2-hydroxyphenyl)-1-phenyl propanone was carried out with DFT using B3LYP method utilizing 6-311++G(d,p) basis set. The structure parameters of the compounds as molecular geometry, bond lengths, bond angles, atomic charge, and HOMO-LUMO energy gap have been investigated and compound with the reported experimental results. The donor and acceptor interactions in 3-(2-Hydroxyphenyl)-1-phenyl propenone were investigated using natural bond orbital (NBO) analysis. By matching the obtained UV-Vis spectra to the time-dependent (TD)-DFT analysis, the energies of band gap, absorption wavelength, and oscillatory strength of 3-(2-Hydroxyphenyl)-1-phenyl propenone were found. Density of states for total (TDOS), partial (PDOS), and also overlap population (OPDOS) analysis were obtained. Molecular electrostatic potential (MEP) provides the information on the electrophilic, nucleophilic, and free radical prone reactive sites of the molecule. Non-linear optical features were demonstrated from the first-order hyperpolarizability. Based on the above results the 3-(2-Hydroxyphenyl)-1-phenyl propenone compound was investigated for further biological investigation. TD-DFT analysis was also performed to calculate energies, oscillator strength of electronic singlet-singlet transitions, and the absorption wavelengths. The Molecular docking (ligand-protein) simulations have been performed using the Auto Dock version 4.2.6. [ABSTRACT FROM AUTHOR]

The target molecule 2,6-bis(4-hydroxy-3-methoxyphenyl)-3,5-dimethylpiperidin-4-one (BHMD) has best binding energy of –7.5 kcal/mol with 5YOK protein of HIV-1 protease. The theoretical studies of the target molecule have been carried out using Gaussian 16W software and viewed by Gaussview 06 software. Bond length, bond angle and dihedral angle of optimized geometry have been performed by DFT method with B3LYP/6-311G (d,p) basis set. The charge transfer and electronic properties of the target molecule have been explained on the basis of highest occupied molecular orbital and lowest unoccupied molecular orbital and its energy values have been used for calculating the global chemical reactivity parameters. In addition to that, molecular electrostatic potential and Mulliken population analysis have been calculated and discussed for predicting the reactive site. NBO analysis has been used to study the charge delocalization and stability of the molecule. NCI and shaded surface map with projection effect of electron localization function have also been studied by Multiwfn 3.8 software. [ABSTRACT FROM AUTHOR]

By using density functional theory (DFT), the FT-Raman, FT-IR, and UV–visible spectra of 1-amino-4-(4-hydroxyphenyl) piperazine (1AM4HPP), 1-chloro-4-(4-hydroxyphenyl) piperazine (1CL4HPP), and 1-methyl-4-(4-hydroxyphenyl) piperazine (1ME4HPP) are carried out. The comparative donor and acceptor interactions are studied for all title compounds using the NBO method. The charge transfer, chemical parameters, and biological activities are examined by highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy results. By density functional theory NLO properties of 1AM4HPP, 1CL4HPP, and 1ME4HPP are studied. The qualitative information of the molecules is carried out using molecular electrostatic potential (MEP) studies. The thermodynamic properties like entropy (S), enthalpy (H), and heat capacity (Cp) are estimated at various temperatures. For each compound, molecular docking is carried out with suitable proteins. [ABSTRACT FROM AUTHOR]

A theoretical study on the thymoquinone compound has been performed through two theoretical methods, DFT/B3LYP and HF with 6-31G, 6-31G(d, p) and 6-31++G(d, p) basis sets using Gaussian 09 program. Some theoretical properties, like vibrational and electronic properties especially UV-Vis and FT-IR spectra, of the title compound were analyzed and then compared with available experimental data. The calculated harmonic vibrational frequencies have been scaled with standard scaling factors 0.9 and 0.965 for HF and DFT/B3LYP, respectively and then compared with available experimental FT-IR spectrum. Furthermore, the statistical analysis was investigated to evaluate the performance of both the HF and DFT methods, including root mean square error (RMSE), mean absolute error (MAE) and mean percentage error (MPE). According to the assigned vibrational modes of the title compound, it could be concluded that the DFT/B3LYP method with 6-31++G(d, p) basis set had the best agreement with experimental data. UV-Vis absorption spectra, excitation energies, maximum absorption wavelength, electronic transitions and oscillator strengths of the title compound were calculated by time dependent density functional theory ( TD-DFT) method using the same basis set and compared with available experimental data. The results showed the best performer was HF method with 6-31G basis set.

Recent joint mass spectrometric and IR photodissociation studies have provided proof on the existence of octa-coordinated ionic lanthanide-carbonyl complexes under those extreme gaseous conditions. In contrast, in older literature concerning cryogenic studies of neutral Ln(CO)x species, the highest coordination was assigned to hexa-coordinated Ln(CO)6 molecules. The present study aims to clarify the above controversy using matrix isolation spectroscopy and DFT calculations. In order to ensure the maximum possible coordination, the Ln(CO)x complexes were synthesized in neat CO cryogenic matrices at 10 K and were investigated by infrared and UV-visible spectroscopy. The formed complexes were identified on the basis of the characteristic CO stretching frequencies of the ground-state molecules predicted by DFT calculations. Our joint experimental–theoretical analysis confirmed the preference of octa-coordinated Ln(CO)8 complexes in cryogenic neat CO matrices. [ABSTRACT FROM AUTHOR]

Propyl gallate was characterized by utilizing quantum computational investigations using the DFT technique and B3LYP/6-311++G (d, p) basis set using GAUSSIAN 16 W software. The FT-IR, FT-RAMAN, UV-Vis, and NMR chemical shifts of propyl gallate were studied theoretically and experimentally. The estimated vibrational wavenumbers were scaled using a suitable scaling factor after the optimized geometrical parameters were determined. FMO and the HOMO-LUMO energy gap were calculated using the TD-DFT method. NBO and NLO properties were also calculated. The reactive sites were predicted using MEP, ELF, LOL, and RDG. Propyl gallate follows Lipinski's rule and has good drug-likeness, according to the bioactivity evaluation. Molecular docking was performed and the protein-ligand binding properties were discussed and compared to pharmaceuticals already in use against COVID-19, which showed good suppression of SARS-CoV-2. Propyl gallate assay studies were used to predict antibacterial and anti-inflammatory properties. These discoveries could help researchers figure out how to employ the title compound to prevent and cure SARS-CoV-2. [ABSTRACT FROM AUTHOR]

In the present study, 3-(4-chlorophenyl)-3-(3,4-dimethoxyphenyl)-1-morpholin-4-ylprop-2-en-1-one (dimethomorph) was characterized by spectroscopic investigations employing FT-IR, FT-Raman, UV-Vis and NMR (13 C, 1H) techniques. The optimized geometrical parameters and complete vibrational assignments of frequencies based on Potential Energy Distribution (PED) were determined by using Density Functional Theory (DFT) through the B3LYP with the level of 6-31G(d) basis set and compared with the experimental values. Besides, to gain better insight into structural features of title composite, HOMO-LUMO bandgap energy and electron excitation analysis was obtained. Molecular Electrostatic Potential (MEP) energy surface and Fukui function descriptor using natural atomic analysis charges were employed to investigate the most reactive sites of the title compound. Natural bond orbital analysis (NBO) elucidates the delocalization of charge due to intermolecular interactions. The topological studies (RDG, ELF and LOL). Molecular docking done with antifungal, antiviral and antimicrobial proteins endorses the bioactivity of molecule. Drug likeness factors were calculated to comprehend the biological assets of dimethomorph. The stability of the title compound has been investigated via molecular dynamics simulations (MDS). In-vitro analysis was done with two fungal pathogens, such as Aspergillus niger and Candida albicans. [ABSTRACT FROM AUTHOR]

The molecular structure of the compound, spectroscopic investigations (FT-IR, FT-Raman, and NMR) and the frontier energy level analysis of 2-(3,4-Dimethoxyphenyl)-3-hydroxy-4H-chromen-4-one (DMP3H), have been all examined using density functional theory (DFT) methods. Comparisons are made between predicted DFT geometrical parameters and experimental values and also the same performed between the theoretical vibrational wavenumbers and observed data. Chemical reactivity of DMP3H has been studied using DFT/PBEPBE approach that includes frontier orbital energies, optical characteristics and chemical descriptors. Additionally, the cytotoxic activity of the bioactive ligand has been checked against human cancer cell lines A549 and MCF-7 in vitro by the MTT assay. Hence, the docking and in vitro activity against cancer cell lines display positive results and the present ligand performance appears to be a promising way for anticancer agents with better efficacy. [ABSTRACT FROM AUTHOR]

In this modest work, a local biopolymer (CHA), biodegradable, non-toxic, and soluble in acidic media, was extracted from the plant Artemisia herba-alba located in the eastern region of Morocco, and characterized by FT-IR, in order to valorize it as a corrosion inhibitor of mild steel in 1 M HCl medium. The electrochemical tests show that the extract is an excellent corrosion protective agent, reaching a maximum value of 96.17% at the concentration of 800 mg/L in the inhibitor. The potentiodynamic polarization (PDP) curves indicate the mixed behavior of the extract, to reduce the current density from 3.445 mA/cm2 to 0.104 mA/cm2 in the presence of 800 mg/L in the inhibitor. The biopolymer CHA of the extract of Artemisia herba-alba undergoes the Langmuir adsorption isotherm, whose adsorption energy is −20.75 kJ/mol, which is attributed to the presence of electrostatic and covalent bonds. In addition, the visualization of the metal surface by a scanning electron microscope (SEM) indicates the formation of a protective layer formed by the extracts of Artemisia herba-alba, which confirms the protective characteristic of the extract used. Theoretical investigations by DFT, MD, and MC confirm previous experimental results. [ABSTRACT FROM AUTHOR]

The density functional theory with the Becke, 3-parameter, Lee–Yang–Parr (B3LYP) technique and the 6-311++G(d,p) basis set is used to optimize the compound 1-Phenyl- 1,3-butanedione (1P1 3B). The 1-phenyl-1,3-butanedione may be obtained in good yield by first preparing a triketone from acetylacetone and a halogenated benzoyl derivative in the presence of a metal halide and tertiary amine in an organic solvent, and then deacetylating the triketone in the presence of an acid. The geometric characteristics of the featured molecule are calculated, and the vibrational frequencies with potential energy distribution (PED) are determined and compared to experimental data. The time-dependent density-functional theory (TD-DFT) technique was used to compute the frontier Molecular Orbitals. Using the HOMO-LUMO energy values, further electronic properties for 1P1 3B were determined. The reactive sites were estimated using the Electron Localisation Function (ELF), and the Molecular Electrostatic Potential (MEP). As a direct consequence of this, the whole molecule's electrophilic and nucleophilic areas have been mapped out. Natural bond orbital (NBO) calculations were used to investigate the delocalization of electron density. The drug likeness features of 1P13B were investigated. The Ramachandran plot is used to study the stability of hydrolase and antibody proteins. The headline molecule is subjected to molecular docking research in order to better understand its biological activities, as well as the minimal binding energy and hydrogen bond interactions.

Conformational changes of 5-chloro-3-nitro-2-hydroxyacetophenone were studied by experimental and theoretical methods. Phototransformations of the compound were induced in low-temperature argon matrices by using UV radiation, which was followed by FT-IR measurements. Two types of changes within the molecule were detected: rotations of the hydroxyl and acetyl groups. A new conformer without an intramolecular hydrogen bond was generated upon irradiation with λ = 330 nm, whereas the reverse reaction was observed at 415 nm. [ABSTRACT FROM AUTHOR]

[Display omitted] • A compound N-(2-carboxylphenyl) phthalimide (CPPD) has been investigated by experimental and theoretical Method. • The compound CPPD showed potent bactericidal activity by Ciprofloxacin since a positive control. S.aureus and S.epidermidis pathogens showed potential activity at concentration of 1 and 2 mg/well, and E.faecalis , P.aeruginosa and E.coli at 2 mg / well. • The compounds CPPD showed hydrogen peroxide (H 2 O 2) scavenging studies value of (42.2 ± 3.1 % to 94.5 ± 2.8 %). • The compound CPPD showed strong DPPH radical scavenging antioxidant activity from 18.2 ± 1.5 % to 73.2 ± 1.7 %. • The Nitric oxide (NO) free radical scavenging property is linearly dependent on CPPD concentration and shown enhancing radical outcomes. • The compound CPPD exhibited the highest ligand-receptor interaction energy value of −7.3 (kcal/mol), 4.39 μM inhibition constant (ki) against high − affinity interaction between target protein (PDB code: 1HD2). The title compound N-(2-carboxylphenyl) phthalimide (CPPD) was purchased with a stated purity of 99 % from M/S. Sigma-Aldrich Co. and utilized as such with no additional purification, CPPD is a thalidomide based derivative, which have led to the uses of most important drugs from 1950 and their mechanisms of action is essential for a better understanding of molecular targets with broad spectrum of biological activity. The obtained FTIR spectral data of the compound were compared to harmonic vibrational frequencies calculated using the ab initio DFT (B3LYP) technique with 6 – 311++G (d,p) basis sets. Furthermore, 13C and 1H NMR, first-order hyperpolarizability (βo) associated parameters (π, α o) of the compound, theSubsequent to recording the molecule'sUV–Visible spectra, DFT was used to analyze its electronic characteristics, including its HOMO and LUMO energies, molecular electrostatic potential (MESP), and Mulliken population studies were using ab initio DFT6-311++G (d,p) basis sets. Pharmacological Screening investigation of the title molecule showed a strong broad-spectrum of antifungal and antibacterial activity against various Gram (+) and Gram (−) bacteria using Ciprofloxacin as a positive control. The headline molecule is subjected to In-silico molecular docking research with the purpose of improved recognize its biological activities, in addition with the minimal binding energy and hydrogen bond interaction that can view by Discovery Studio 4.0 visualizers. and drug likeness using Swiss ADME predictor (http://www.swissadme.ch/index.php) along with AdmetSAR-2.0 online software analysis tools features were investigated. The compound CPPD's ability to degrade DPPH increased as a dose-dependent manner, with its maximal DPPH scavenging characteristic spanning from (18.2 ± 1.5 % to 73.2 ± 1.7 %) and maximum H 2 O 2 scavenging trait ranging from (35.5 ± 5.3to 88.8 ± 3.1 %). The NO free radical scavenging property is linearly dependent on CPPD concentration. The interaction between the CPPD ligands and the 1HD2 protein is demonstrated by these data, as the protein displays a reduced binding energy value of −7.3 (Kcal/mol) and an inhibitory constant (k i) value of 4.39 μM. In swiss ADME prediction, CPPD is an evident from the physicochemical data that has an efficient receptor site binding mechanism. The lipophilicity of a drug is determined by its partition coefficient (Log P= log Po/w) between water and N-(2-carboxylphenyl) phthalimide. The paper further explains that the title compound can act as promising antibacterial and antioxidant agent through in-vitro and molecular docking studies. [ABSTRACT FROM AUTHOR]

A series of 3‐allyl‐2,6‐diarylpiperidin‐4‐one derivatives were designed and synthesized as antimicrobial agents with good yields. The target compounds were characterized by Mass, NMR, FT‐IR and FT‐Raman spectral techniques. The optimization had been performed on the title compound using the B3LYP method with 6‐311++G(d,p) basis set. The optimized bond parameter of the title molecule was calculated by DFT method. To study the intramolecular charge transfer within the molecule, the Lewis (bonding) and Non‐Lewis (anti‐bonding) structural calculation was performed. The Non‐linear optical behaviour of the title compound was measured using first order hyperpolarizability calculation. Mulliken atomic charges and thermodynamic properties were also calculated and analyzed. In vitro antibacterial and antifungal screening for all the synthesized 3‐allyl 2,6‐diaryl piperidin‐4‐ones was evaluated for two Gram‐positive bacteria (Staphylococcus aurous, Enterococcus faecalis), three Gram‐negative bacteria Pseudomonas aeruginosa, Escherichia coliand K. pneumonia) and five fungi (Candida albicans, Aspergillus niger, Aspergillus flavus, Rhizopus sp and Mucor sp). All the compounds showed good antibacterial and antifungal activities. Molecular docking study is to demonstrate that piperidine derivatives bind to Ribonucleotide reductases (RNRs) enzymes and to evaluate whether these molecules can be used as potential drugs. [ABSTRACT FROM AUTHOR]

Fourier transform infrared spectra, for 2-((2-aminopyridin-3-yl) methylene) hydrazinecarbothioamide (APHT) and 2((2-aminopyridin-3-yl) methylene)-N-methylhydrazinecarbothioamide (APMHT), were recorded in the spectral range 4000–400 cm−1. Their Raman counterparts were measured in the spectral region 4000–50 cm−1. Preliminary values of dihedral angles around five rotating bonds C–NH2 pyridyl C–CN, N–N, N–CS and C–NH2 aliphatic in APHT, required for initiating geometry optimization, were obtained by pairing successive bonds and evaluating torsional potential energy for various values of dihedral angle around these bonds in the entire conformational space spanning 0° to 360°. Barrier heights, around five rotating bonds in APHT and six rotating bonds in APMHT were computed, making torsional scans in conformational space from 0° to 360°. This indicated existence of two rotational isomers for APMHT. General valence force field, harmonic vibrational fundamentals, potential energy distribution (PED), along with infrared and Raman intensities were determined using DFT/B3LYP/6-311++G(d,p) level of theory for both the molecules. Good agreement was found between measured and simulated spectra, for APHT and APMHT. This was also true for corresponding Raman spectra. The rms error between experimental and theoretical vibrational frequencies was 9.00 and 6.70 cm−1, for APHT and APMHT, respectively. All vibrational fundamentals were assigned unambiguously, on the basis of computed PED, eigenvectors, and literature range for the first time. These assignments were further supported by comparing with attribution of corresponding bonds in the parent molecule pyridine and a related molecule 2-((2-aminopyridin-3-yl)methylene)-N-ethylhydrazinecarbothioamide, wherever possible. [ABSTRACT FROM AUTHOR]

In this work, 4-(((4-ethyl-5-(thiophen-2-yl)-4H-1,2,4-triazole-3-yl)thio)methyl)-7,8-dimethyl-2H-chromen-2-one was synthesized by acetone-mediated condensation of 4-ethyle-5-(thiophen-2-yl)-4H-1,2,4-triazole-3-thiol and 4-(chloromethyl)-7,8-dimethyl-2H-chromen-2-one. The molecule results (3) were experimentally characterized using FT-IR, 1H-, and 13C NMR spectroscopy. Density Functional Theory (B3LYP/cc-pVDZ) was used to investigate the ideal molecule structure, vibrational frequencies, and 1H with 13C NMR (theoretically) chemical shifts. Theoretical and experimental spectroscopy results were compared and agreed with each other, which indicated the validity of the used developed molecular structure. The Dipole moment, hardness, softnes, electronegativity, electrophilicity index, nucleophilicity index, and chemical potential as electronic structural parameters linked to corrosion inhibition efficacy were investigated for the prepared compound. Furthermore, the fraction of transferred electrons was calculated to determine the interaction between the iron surface and organic molecules. The results indicated a favorable relationship between organic-based corrosion inhibitors and quantum chemical parameters processes. The corrosion inhibitors' behavior can be predicted without the need for experimental investigation.

An organic crystalline salt − 2,4-Diamino-6-methyl-1,3,5-triazin- 1-ium hydrogen oxalate (DMTO) has hydrogen interactions viz. NH⋯O, CH⋯O, NH⋯N and OH⋯O gives interesting vibrational effect. X-ray diffraction study reveals that DMTO is crystallized in triclinic centrosymmetric space group P-1 as expected. Structural as well as the vibrational spectra have been discussed on the basis of density functional theory (DFT) using B3LYP hybrid functional with the basis set 6–311++G(d,p). Acidic proton of the oxalic acid (OA) is transferred to 2,4-diamino-6-methyl-1,3,5-triazine (DAMT) and giving rise to singly protonated 2,4-diamino-6-methyl-1,3,5-triazinium ion.

Recent joint mass spectrometric and IR photodissociation studies have provided proof on the existence of octa-coordinated ionic lanthanide-carbonyl complexes under those extreme gaseous conditions. In contrast, in older literature concerning cryogenic studies of neutral Ln(CO)x species, the highest coordination was assigned to hexa-coordinated Ln(CO)6 molecules. The present study aims to clarify the above controversy using matrix isolation spectroscopy and DFT calculations. In order to ensure the maximum possible coordination, the Ln(CO)x complexes were synthesized in neat CO cryogenic matrices at 10 K and were investigated by infrared and UV-visible spectroscopy. The formed complexes were identified on the basis of the characteristic CO stretching frequencies of the ground-state molecules predicted by DFT calculations. Our joint experimental–theoretical analysis confirmed the preference of octa-coordinated Ln(CO)8 complexes in cryogenic neat CO matrices.

• Computed and experimental spectroscopic (Raman, FTIR, UV, and NMR) characterization has been carried out on 4-Methyl-N-pyridin-2-yl-benzenesulfonamideyde • ELF-LOL, RDG, confirmed chemical reactivity and the kinetic stability of the compound. • NBO study helped in examining the stabilization energy. • Drug likeliness, ADMET, Ramachandra plot and Molecular docking analysis ascertained the bioactivity of the molecule In this section, the spectroscopic characteristics of 2-amino-toysl-pyridine (2ATP) are fully examined, using both experimental and computational investigations guided by density functional theory (DFT). It will facilitate our computational research using the B3LYP approach to use the basis set 6–311++G(d,p). Comprehensive assignments of vibrational modes were obtained from the vibrational spectra, which comprised FT-Raman and FT-IR spectroscopy and were recorded in the region of 3500–400 cm−1 and 4000–500 cm-1, respectively, using the Vibrational Energy Distribution Analysis (VEDA) approach. The net atomic charges inside the molecule were ascertained by using Mulliken population analysis, natural atomic charges, and electrostatic potentials (CHELPG). The structural conformations of 2ATP were determined using NMR spectroscopy in a CDCl 3 solvent. The donor-acceptor interactions of the 2ATP molecule at the 6–311++G(d,p) level were studied by means of a Natural Bond Orbital (NBO) study. Studies of the ultraviolet (UV) spectrum in ethanol were used to assess the effects of the solvent. An assessment was made of the energy difference between the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) in order to understand charge transfer processes that suggest the molecule may have biological activity. Molecular electrostatic potential (MEP) surfaces were used to predict the nucleophilic and electrophilic sites in molecules. The non-covalent interactions were evaluated using the reduced density gradient (RDG) approach. The Multiwfn software was used to analyze the topological properties of the 2ATP, including the Localized Orbital Locator (LOL) and Electron Localization Function (ELF). Further attention was drawn to the compound's exceptional pharmacological potential when its ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) characteristics were evaluated. Not to add, molecular docking experiments were carried out to evaluate the feasibility of 2ATP as a bioactive material with possible uses in the pharmaceutical business. [ABSTRACT FROM AUTHOR]

• FT-IR, FT-Raman and UV–Vis spectra of methyl indole 3-Carboxylate were reported. • Mulliken and FMOs confirms the intramolecular charge transfer of the molecule. • MEP analysis confirms the reactive sites of the MIC molecule. • Docking results show that the molecule can be useful for the cervical cancer. Bioactive indole derivatives had great importance in recent years due to their numerous biological and pharmaceutical applications. In the present work, the vibrational, electronic, physicochemical, and inhibitory properties of the Methyl Indole-3-Carboxylate (MIC) molecule were predicted and analyzed. Initially, the molecular structure of the title molecule was optimized and its structural parameters were calculated, which were highly correlated with the previous reports. The simulated infrared and Raman spectra of the molecule were in good agreement with the FT-IR and FT-Raman spectra that were observed via the experiment. The observed UV–Visible spectrum validates the MIC molecule's π→π* electronic transition, which was also well matched with the simulated UV–Visible spectrum. The investigation of frontier molecular orbitals highlights intramolecular charge transfer across the molecule, establishing the bioactivity of the MIC molecule. The electron transport from the methyl group hydrogen atom H22 to the oxygen atom O11 is confirmed by Mulliken atomic charge distribution analysis and molecular electrostatic potential surface analysis. The calculated Fukui functions values validated the FMOs and Mulliken atomic charge distribution results. The natural bond orbital study further confirms the MIC molecule's intramolecular charge transfer and bioactivity. Molecular docking investigation results that the MIC molecule hinders the function of an enzyme known as Mitogen-activated protein kinase 14, which has been linked to cervical cancer. As a result, the present study provides the possibility towards the development of innovative to treat cervical cancer. [ABSTRACT FROM AUTHOR]

Synthesis, X-ray crystallography, spectral analysis, and molecular docking analysis on (E)-2-(1-(4-fluorophenyl) ethylidene) hydrazine carbothioamide (EFEHC) are performed. Thiosemicarbazones are a class of small molecules used as anticancer therapeutics. The FT-IR and FT-Raman spectra of EFEHC have been recorded in 4000-400 and 4000-100 cm-1, respectively. The present communication deals with the quantum chemical calculations of energies, geometrical structure, and vibrational wavenumbers of EFEHC using the density functional (DFT/B3LYP) method with 6-31G (d, p) basis set. The conformational analysis gives the energy values based on the change in the position of atoms in the EFEHC molecule. Hirshfeld surface analysis (HSs) is used to discuss the evaluation of intermolecular interactions. Molecular docking analysis of the small molecule EFEHC with macromolecule HMG-CoA protein showed that this is a good molecule and is suitable for anti-cholesterol targets. [ABSTRACT FROM AUTHOR]

Fourier transform infrared (FT-IR) and Raman (FT-Ra) spectra of 1-(4-methoxyphenyl)-1H-imidazole were recorded and analyzed. The vibrational wavenumbers of the structure were computed by using the density functional theory (DFT)/Becke three Lee–Yang–Parr (B3LYP)/6–311 ++ g(d,p) basis set. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy values were determined to be − 1 eV and − 6.27 eV, respectively. The HOMO–LUMO energy gap value was found to be 5.27 eV. A large HOMO–LUMO gap means low reactivity in chemical reactions, indicating the high stability of the molecule. The HOMO–LUMO energy gap for the existing structure is relatively high, as a result the title molecule is hard. 1H, 13C NMR, and UV–Vis experimental and theoretical spectral analyses were given. Molecular electrostatic potential, Fukui functions, and charge analysis were performed to predict electrophilic and nucleophilic regions or atoms. The nonlinear optical properties of the structure were investigated, and it was found that the structure showed an important nonlinear optical property. Basic thermodynamic properties such as entropy (S), enthalpy changes (ΔH), heat capacity (Cp), Gibbs free energy (G), and zero-point vibration energy were calculated under constant pressure in the gas phase for different temperature values. It was determined that this compound has a significant antibacterial effect against some bacterial strains. Also, to support the antibacterial activity studies of the title molecule, molecular docking studies were carried out with protein structures of some microorganisms used in the antibacterial activity studies. [ABSTRACT FROM AUTHOR]

Terra preta is a fertile anthropogenic soil found in the Amazon basin. One of the most significant differences between the terra preta and surrounding soils is that terra preta is rich in aromatic carbons. Previous infrared investigations of terra preta were reported at energies above 1000 cm−1 where many other forms of carbon also have absorption lines. No measurements have been reported below 800 cm−1, where many absorptions associated with aromatic carbons occur in the absence of aliphatic carbon lines. We employ Fourier transform infrared spectroscopy between 150 cm−1 and 500 cm−1. A comparison was made between the spectra of terra preta, several pure aromatic compounds, organic fertilizers developed to replicate terra preta and several Australian soils, some of which containing char from bushfires. The spectra in the 150–500 cm−1 range were very similar between terra preta and the organic fertilizers, while they were very different for the natural soils. These findings indicate that the content of aromatic carbons in terra preta and organic fertilizers is different than in natural soils containing the bushfire chars, but also soils produced entirely by bacterial and fungal activities. This point to the importance of the preparation conditions of the biochars, which are essential ingredients of terra preta and organic fertilizers used in this study. Graphical Abstract [ABSTRACT FROM AUTHOR]

In biomedical applications, Cu2O nanoparticles are of great interest. The bioengineered route is eco-friendly for the synthesis of nanoparticles. Therefore, in the present study, there is an attempt to synthesis Cu2O nanoparticles using Datura metel L. The synthesized nanoparticles were characterized by UV–Vis, XRD, and FT-IR. UV–Vis results suggest the presence of hyoscyamine, atropine in Datura metel L, and also, nanoparticles formation has been confirmed by the presence of absorption peak at 790 nm. The average crystallite size (19.56 nm) was obtained by XRD. FT-IR was also used to confirm the different functional groups. Fourier Power Spectrum was also employed to examine the synthesized nanomaterials spectrum data to emphasize the peak of the prominent frequencies. Density functional theory (DFT) was also utilized to assess the energy of the substance over time, which appears to indicate a stable molecule. Furthermore, calculated energies, thermodynamic properties (such as enthalpies, entropies, and Gibbs-free energies), modeled structures of complexes, crystals, and clusters, and predicted yields, rates, and regio- and stereospecificity of reactions were all in good agreement with experimental results. Overall, the results show that the successful production of Cu2O nanoparticles with Datura metel L. corresponds to theoretical research. [ABSTRACT FROM AUTHOR]

The aim of this work is to investigate the structural and chemical behavior of the novel N4,N4′-dimethyl-[1,1′-biphenyl]-3,3′,4,4′-tetraamine (NNDMTA) compound using experimental and computational method. The synthesized compound has been characterized by FT-IR, NMR and UV-Visible spectroscopy method. The geometry structure was optimized by means of on density functional theory (DFT) and time depended density functional theory (TD-DFT) method with the ultrafine grid method. The theoretically computed spectroscopic properties (FT-IR, NMR UV-visible) of the compound was compared with experimental results and were found to be in accord. The complete vibrational frequency assignments were carried out using Vibrational Energy Distribution Analysis 4 (VEDA 4) program. The electronic absorption behavior of the compound has been performed by the TD-DFT method. Global chemical reactivity descriptors (GCRD) parameters and activity site of the compound has been discussed. Further, intermolecular interaction and molecular reactive behaviors toward electrophiles have been reported. Besides, molecular physicochemical, absorption distribution metabolism and excretion (ADME) and molecular docking analysis were also carried using Molinspiration, Swiss ADME and Patchdock methods respectively. The results have shown the highest atomic contact energy for the human squalene synthase (−246.41 kcal/mol) and the least atomic contact energy for the influenza neuraminidase (−57.88 kcal/mol). [ABSTRACT FROM AUTHOR]

In the present work, the molecules, (E)-1-(4,4″-difluoro-5′-methoxy-1,1′:3′,1″-terphenyl-4′-yl)-3-phenylprop-2-en-1-one (DFTP), (2E)-1-(4,4″-difluoro-5′-methoxy-1,1′:3′,1″-terphenyl-4′-yl)-3-(4-fluorophenyl)prop-2-en-1-one (TFTP), (2E)-3-(4-bromophenyl)-1-(4,4″-difluoro-5′-methoxy-1,1′:3′,1″-terphenyl-4′-yl)-prop-2-en-1-one (BFTP), and (E)-1-1(4,4″-difluoro-5′-methoxy-1,1′:3′-1″-terphenyl-4′-yl)-3-(4-methylphenyl)prop-2-en-1-one (FMTP) have been synthesized and vibrational wavenumbers and electronic properties have also been performed. The compound series shows good light harvesting properties and photovoltaic modeling shows that they can be used successfully in DSSCs as photo sensitizers. The NLO activity of the title compounds have been investigated and β and γ values varies in the order BFTP > FMTP > TFTP > DFTP. The consequences which were made by electron donor acceptor due to charge transfer mechanism have been scrutinized by the natural bond investigation. Molecular docking has been performed to understand the binding interactions of the analyzed ligands with tyrosine-protein kinase JAK2 and these compounds can be developed as anticancer agent. [ABSTRACT FROM AUTHOR]

The molecular vibrations of diphenylhydantoin (DPH) were investigated in crystalline sample at room temperature, by using Fourier transform infrared (FT-IR), FT- and conventional Raman spectroscopies. Furthermore, density functional theory (DFT) calculations were utilized to confirm and clarify the experimental data. Two methods were evaluated for accurate prediction of the vibrational spectra: i) vibrational anharmonic calculations on DPH monomer based on the second-order perturbation theory; ii) harmonic calculations on a cluster of five DPH molecules. [ABSTRACT FROM AUTHOR]

The vibrational spectroscopic (FT-IR and FT Raman) and electronic properties (UV-Vis) have been investigated experimentally at room temperature and were compared with quantum computational calculations using DFT and TD DFT techniques with 6-311++G(d,p) as the level of theory by GAUSSIAN 09W. The fundamental modes of vibrations were carefully assigned which were compared with experimental vibrations. Theoretical information on the optimized structure, Natural Bond Orbitals (NBO) and NLO were also obtained. The delocalization of electrons due to hyper conjugation was understood using NBO analysis. Data on the stabilization of the molecule due to different transitions were explained using this analysis. Dipole moment, polarizability and first order hyperpolarizability calculations were done. These revealed that the compound may be a suitable NLO material. Thermodynamic properties such as entropy, enthalpy and specific heat of molecule over a temperature range 100-1000 K were studied. The compound was found to be stable for higher temperature range. Local reactivity sites of the compound were studied using Molecular Electrostatic Potential (MEP) and Localized Orbital Locator (LOL) studies, while Pauli exchange repulsion effect was used to obtain Electron Localization Function (ELF). Hence the electrophilic and nucleophilic sites of the molecule were elucidated. A Hirshfeld surface was obtained to study the intermolecular interactions. The HOMO-LUMO energy gap was calculated and compared with the experimental data obtained and was found to be in good agreement. An electrophilicity index of 3.439 explains that the molecule is biologically active. The drug-like nature of the molecule was confirmed using Lipinski's rule of five. Hence, the protein binding orientations and energies of protein-ligand complexes were predicted using molecular docking studies. [ABSTRACT FROM AUTHOR]

In this present look at on 4-(Trifluoromethyl)phenylacetonitrile (4TFMNB) has been investigated with the aid of FT-IR, FTRaman and NMR (¹H and 13C) spectral works. Most of the vibrational assignments of FT-IR and FT-Raman spectra predicted using density functional theory (DFT) method match well with experimental findings. The 13C and ¹H NMR chemical shifts of the title compound is obtained by the gauge independent atomic orbital (GIAO) method and compared with experimental results. [ABSTRACT FROM AUTHOR]

Herbacetin (HBN) is an antiviral agent of H1N1 influenza virus which was reported to inhibit H1N1 neuraminidase (NA) enzyme with IC50 value of 8.9 μM. The research exploration for HBN was conducted via quantum chemical calculations and spectroscopic techniques. The experimental vibrational FT-IR and FT-Raman spectra of the HBN molecule were obtained, and it was compared with theoretical method utilizing quantum chemical calculations through DFT approach employing basis sets 6-31G(d,p) and 6-311G(d,p). The MEP, NBO, global and local reactivity descriptors were carried out to describe the reactivity, selectivity and stabilization of the HBN molecule. The electronic characteristics namely UV-Vis and HOMO-LUMO were computed through TD-DFT method which was correlated with experimental spectral analysis. The total, partial and overlap population density of states (DOS) were carried out to confirm the molecular orbital contributions. The drug likeness and ADMET predictions were analysed to reveal the biological behaviour of the HBN. Furthermore, the molecular docking investigation is to find the best fit orientation: binding mode, inhibition constant and intermolecular interactions among HBN and NA enzyme. The ligand molecule fits very well in the NA active site cavity. Hence, the HBN molecule exhibits good biological activity, and it can be served as a prospective drug for H1N1 influenza A virus. [ABSTRACT FROM AUTHOR]

The optimized parameters, the vibrational wavenumbers of 6-chloro-3-Pyridinecarbonitrile were determined by utilizing density functional method. Vibrational task of the molecule was finished by utilizing potential energy distribution examination. Natural bond orbital examination, Mulliken charge investigation and Frontier Molecular Orbital energy were utilized to explain the reasons for intra molecular charge move. Complete vibrational tasks of the molecule have been done based on the potential energy distribution. The molecular electrostatic potential mapped onto complete density surface has been acquired. The various intramolecular interactions have been exposed by natural bond orbital analysis. Docking studies were conducted to predict its anticancer activity. [ABSTRACT FROM AUTHOR]

The CMC/PAM-Co3O4 nanocomposites were prepared using the casting method. The interaction between Co3O4 and CMC/PAM was analysis and characterized using DFT calculation with FT-IR spectroscopy, UV–Vis analysis and AC conductivity. The interaction between CMC/PAM blend and Co3O4 nanoparticles was occurs and confirmed by DFT calculations due to the presence of OH group in CMC and NH2 group in PAM. The values of the optical band gap (Eg) were decreased as an increase of Co3O4 NPs reflects the effect of the nanoparticles in the modification of electronic structure and the response of Co3O4 NPs to the form of localized electronic states. The values of the optical energy gap were reduced after the addition of Co3O4 nanoparticles. Meanwhile, the electrical conductivity of CMC/PAM-Co3O4 was increased with an increase of Co3O4 NPs at room temperature. The AC conductivity and the dielectric properties were carried out of the nanocomposite films, an enhancement was observed in both values of the dielectric constant ϵ ′ and the dielectric loss ( ϵ ″) after the addition of Co3O4 NPs. [ABSTRACT FROM AUTHOR]

Uracil-based compounds have increasing attention in material design for different applications as well as pharmaceutical purposes. Accordingly, the key electronic reasons underlying the solvatochromic effect and possible activity features by using quantum chemical computations should be explored in detail. This work focuses on the structural, electronic, and optical properties of the aminouracil derivatives to explore the key electronic-related properties that affect the solvatochromism features. The molecular geometries of the 1,3-dimethyl-5-(arylazo)-6-aminouracil derivatives were optimized using the DFT method at the B3LYP/6–31++G(d,p) basis set level. The solvent-phase simulations of the studied derivatives were utilized using the PCM (Polarized Continuum Model). The TD-DFT approach was employed to enlighten UV–visible characteristics such as possible electronic transitions, energies, and oscillator strengths. The NBO (Natural Bond Orbital) method was used to predict the possible intramolecular charge transfer and delocalization, as well as the interactions between donor-acceptor molecular orbitals. TD-DFT computations revealed that the bonded group within the arylazo ring would affect solvatochromic properties such as electronic excitation energies and transitions in the UV-Vis regions. The NBO analysis revealed that the electron movement from the lone pair of N atoms on the uracil unit to neighbor unfilled orbitals contributed to reducing the stabilization energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Aromatic sidechains provide additional stabilisation of hydrogen-bonded complexes. • The solvent effect is the main factor that distinguishes formation constants in PCA. • Theory predicts a greater impact of resonance than experimentally observed. • Surface area, partial charge and inductive descriptors show the best correlation. In this research, experimental and theoretical spectral analysis of N -monosubstituted benzamides was performed by mid-infrared spectroscopy and density functional theory. The MIR spectroscopic characteristics for N–H∙∙∙O, N–H∙∙∙N and N–H∙∙∙π hydrogen-bonded complexes and also the equilibrium constants for 1:1 complex formation are given. The structures of selected N -substituted benzamides (as proton donors), benzene, acetonitrile, and tetrahydrofuran (as proton acceptors), as well as their complexes, were optimised at the M06-2X/6–311++G(d,p) level of theory. The solvent effect on hydrogen-bonded complexes and the correlations between the equilibrium constants and molecular descriptors of N -monosubstituted benzamides were also investigated using a principal component analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimized structure monomer and dimer structures of A10 DLC using DFT. • Microscopic molecular dynamics were revealed through FT-IR, FT-Raman, and DFT. • Predicted the mesomorphic models of nematic and columnar of A10. • QTAIM analysis predicts the strength and nature of hydrogen bonding. Utilizing temperature-dependent Fourier Transform Infrared (FT-IR) and Fourier Transform Raman (FT-Raman) spectroscopies, we delved into the spectral properties of 4-((2,3,4-tris(decyloxy)phenyl)diazenyl)benzoic acid, a fascinating discotic liquid crystal (DLC) named A10. Our investigation unravels valuable insights into conformational dynamics, intermolecular hydrogen bonding, and structural stability, throughout enantiotropic phase transitions (Isotropic (Iso) → Discotic Nematic (N D) → Columnar (Col) → Crystalline (Cry)) during cooling. To further understand the mesogen's phasmid structure at atomic level, density functional theory (DFT) is employed, utilizing the B3LYP/6-3116G(d,p) method for optimization and frequency calculations of monomer and dimer of A10. The alignment of computationally predicted molecular models with observed vibrational spectra at room temperature affirms the precision of our theoretical model. Innovatively, our study has uncovered the potential formation of dimer assemblies, demonstrating the persistence of intermolecular hydrogen bonding within these dimers throughout each phase transition of the DLC. Furthermore, we have identified the strength of both intermolecular and intramolecular hydrogen bonding. These findings expand our knowledge of this unique material and pave the way for further research in the field of liquid crystals. [ABSTRACT FROM AUTHOR]

A novel Schiff base derivative, 4,4'-(propane-1,3-diylbis(azanylylidene))bis(naphthalen-1(4H)-one) (PAN), was synthesized from the reaction of 1,4-naphthoquinone with 1,3-diaminopropane. Synthesized substance was characterized by using 1H and 13C NMR, FT-IR, UV–Vis spectroscopies and elemental analyses. Optimized geometry, geometric parameters, molecular electrostatic potential (MEP) diagram and vibrational wavenumbers of the PAN were calculated by using Density Functional Theory (DFT) at B3LYP/6-311G(d,p) level. 1H- and 13C-NMR chemical shifts were theoretically obtained using the gauge independent atomic orbital (GIAO) method with mentioned level of theory. Furthermore electronic transitions, frontier molecular orbital energies (FMOs) such as HOMO and LUMO were also calculated by time-dependent DFT (TD-DFT) approach. Theoretically calculated spectroscopic data were found to be quite compatible with those obtained experimentally. [ABSTRACT FROM AUTHOR]