Dipole Moment Parameters Research Articles

Cavity ring-down spectroscopy of 14N216O near 0.83 µm

The cavity ring-down spectra (CRDS) of nitrous oxide were recorded at a pressure of 10 hPa in the 11,937–12,223 cm-1 range with a threshold sensitivity to absorption coefficient of the order of 6.5 × 10–11 cm-1. Three bands (ν1+5ν3, 6ν1+2ν3, and 3ν1+4ν3) were detected. The line centers and intensities were recovered from the observed spectra. The spectroscopic constants of the upper vibrational states and the vibrational transition dipole moment parameters were fitted to the measured line positions and intensities, respectively. It was found that the 3ν1+4ν3 band is in the interpolyad Coriolis resonance interaction with the 7ν1+7ν21 band. This interaction leads to the appearance in the spectra of the four extra lines of the 7ν1+7ν21 band.

Assignment and modeling of 13CH4 spectrum at 298 K in the lower part of the Tetradecad in the 4970–5300 cm−1 range

The absorption spectrum of the 13CH4 methane isotopologue was recorded on a Bruker IFS-125HR Fourier transform spectrometer at 298 K in the 4970–6200 cm−1 range. In this paper we report the results of assignment and modelling of the line positions and intensities of 13CH4 in the range of weaker absorption between 4970 and 5300 cm−1, corresponding to the lower part of Tetradecad, dominated by the 4ν4 band system near 5180 cm−1. The empirical list in this spectral range contains 1642 lines. Using an effective Hamiltonian initially derived from the analyses of cold Fourier transform (4970–5853 cm−1) and laser direct absorption (5853–6200 cm−1) spectra of the 13CH4, we assigned 1600 lines belonging to four bands of the Tetradecad up to Jmax=16. The 1548 line positions were fitted with an rms deviation of 1.7 × 10−3 cm−1. Measured line intensities were modeled for 674 transitions using the effective dipole transition moments to an rms deviation of about 7 %. The new data were used for the simultaneous global fit of the 13CH4 Hamiltonian parameters for the {Ground state / Dyad / Pentad / Octad / Tetradecad} system and the dipole moment parameters for the {Ground state - Tetradecad} system.

Cycloadditions of 4-Alkenyl-2-aminothiazoles with Nitroalkenes in the Formal Synthesis of Pramipexole: An Experimental and Computational Study.

4-Alkenyl-2-dialkylaminothiazoles act as in-out dienes in [4 + 2] cycloaddition reactions with nitroalkenes, furnishing 2-amino-6-nitro-4,5,6,7-tetrahydrobenzothiazoles in moderate to good yields, accompanied by a subsequent 1,3-H migration. These transformations proceed with exquisite site-, regio-, and diastereoselectivity. This strategy is further enriched by revealing a novel route for pramipexole synthesis. The examination of the potential energy surfaces associated with the four possible reaction pathways for the Diels-Alder cycloaddition (relative approach of the diene-dienophile and endo/exo approach of the nitro group) not only aligns with experimental observations but also unveils key mechanistic insights. Specifically, computational analyses uncover the favored pathway yielding 6-nitro-4,5,6,7-tetrahydrobenzothiazoles, with some instances proceeding through a two-step mechanism involving a tandem sequence of chemical processes, and the influence of various factors such as dienophile structure and the approach mode of the nitro group. Additionally, the stabilization of the exo-transition states, particularly facilitated by phenyl substitution in the dienophile, is highlighted. Asynchronicity, dipole moment, and other parameters indicative of polar character further characterize these Diels-Alder reactions. Conceptual DFT calculations underscore the pivotal role of the 1,3-thiazole ring in enhancing dienic activation and dictating regioselectivity, emphasizing interactions between the C5 of the thiazole nucleus and the Cβ atom of the nitroalkenes.

Design and Synthesis of Pyridine Bis-Hydrazone Metal Complexes of Co(II), Cu(II), and Hg(II): Spectral, Gaussian, Electrochemical, Biological, Drug-Likeness and Molecular Docking Investigations

A bis-hydrazone ligand (H2DS) was synthesized via condensation of pyridine-2,6-dicarbohydrazide with salicylaldehyde and utilized to prepare a new series of Cu(II), Co(II), and Hg(II) metal chelates. All the prepared chelates were investigated using various assistive spectroscopic and microscopic tools including (1H, 13C -NMR, IR, UV–visible, ESR, XRD, EDX, SEM, and MS), elemental analysis, magnetic susceptibility, and thermal (TG/DTA) analysis. Furthermore, all of the previous structural investigations weresupported with theoretical studies based on DFT theory where the molecular modeling of the geometrically optimized structures was constructed through Gaussian 09 software. Various energy components such as (EBinding, EHOMO, and ELUMO) besides MEP (Molecular electrostatic potential), bond parameters (bond angle and bond length), dipole moment, and molecular chemical parameters were derived from the computational calculations. Moreover, the redox behavior of Cu(II) with/without the ligand (H2DS) was investigated using cyclic voltammetry. This technique is utilized to study the effect of the chelating agent on the attitude of the copper species in the solution universe. The impact of interaction is proved by changing in the potential of reduction/oxidation peaks alongside evaluating of both kinetic and thermodynamic stability. The produced hydrazone and its chelates were screened for antimicrobial activities (Escherichia coli, Staphylococcus aureus, and Candida albicans), antioxidant activities (DPPH and TAC), and cell viability MTT assay. Finally, the degree ofefficiency of the binding that occurs between the different protein receptors and the ligandwas estimated by molecular docking where the results showed a strong relationship with the biological investigations.

Unrivaled accuracy in measuring rotational transitions of greenhouse gases: THz CRDS of CF4.

Tetrafluoromethane CF4 is the most abundant perfluorocarbon in the atmosphere, where it is designated as PFC-14. This greenhouse gas is very stable, has an atmospheric lifetime of 50 000 years, and a high greenhouse warming potential 6500 times that of CO2. Over the last 15 years, its atmospheric concentration has increased at a rate of 0.8 ppt per year. The accurate quantification of CF4 is key to understanding the contribution of its emissions to the radiative forcing budget, and the most precise spectroscopic parameters possible are hence required. In this study, a novel high finesse THz cavity, providing an interaction length in excess of 1 km, has enabled highly resolved spectra, and quantification of the weak transitions of CF4 by cavity ring-down spectroscopy (CRDS). More than 50 pure rotational P6 - P6 : ν3 - ν3 lines of CF4 have been measured, yielding both position and intensity with unequalled precision. Several tetrahedral splittings are fully resolved and measured with sub-MHz accuracy. Moreover, CRDS-THz allows determining absolute intensities and, using a global fit of the ν2 polyad series, a CF4 dipole parameter, namely 3,3, has been fitted to 106.38(53) mD. This value is in very good agreement with that of the ab initio-based parameter deduced from a dipole moment surface. For the first time, a set of ab initio effective dipole moment parameters is derived for the computation of the transitions of the type Pn - Pn (n = 0,…, 8) and the resulting line list composed of 25 863 transitions can be used to model the whole CF4 rotational spectrum. Finally, the TFMeCaSDa database is updated and is available for future spectroscopic and monitoring activities.

Application of chemometric tools in the QSAR development of VOC removal in plastic waste recycling

Deodorization and, in a broader sense, the removal of volatile organic compounds (VOCs) from plastic waste have become increasingly important in the field of plastic recycling, and various new decontamination techniques have been developed. Both in research and industrial practice, the selection of VOCs has been random or unsubstantiated, making it difficult to compare studies and assess decontamination processes objectively. Thus, this study proposes the use of Statistical Molecular Design (SMD) and Quantitative Structure - Activity Relationship (QSAR) as chemometric tools for the selection of representative VOCs, based on physicochemical properties. Various algorithms are used for SMD; hence, several frequently used D-Optimal Onion Design (DOOD) and Space-Filling (SF) algorithms were assessed. Hereby, it was validated that DOOD, by dividing the layers based on the equal-distance approach without so-called ‘Adjacent Layer Bias’, results in the most representative selection of VOCs. QSAR models that describe VOC removal by water-based washing of plastic waste as a function of molecular weight, polarizability, dipole moment and Hansen Solubility Parameters Distance were successfully established. An adjusted-R2 value of 0.77 ± 0.09 and a mean absolute error of 24.5 ± 4 % was obtained. Consequently, by measuring a representative selection of VOCs compiled using SMD, the removal of other unanalyzed VOCs was predicted on the basis of the QSAR. Another advantage of the proposed chemometric selection procedure is its flexibility. SMD allows to extend or modify the considered dataset according to the available analytical techniques, and to adjust the considered physicochemical properties according to the intended process.

Divalent transition metal complexes of nitrogen, oxygen and sulfur containing ligand: design, structural, spectral, pH-metric, theoretical molecular modeling, analytical and mechanism studies

In the present study, the 1-Nicotinoyl-4-phenyl thiosemicarbazide (H2NPT) multidentate nitrogen, oxygen and sulfur containing ligand is being synthesized in a simple single step reaction by condensing 1:1 molar ratio of ethanolic solutions of both phenyl isothiocyanate and nicotinoyl hydrazine. The prepared H2NPT and its complexes with Co2+, Ni2+ and Zn2+ and Cu2+ were characterized by pH-metric titrations, elemental analysis, FTIR, electronic spectra and thermogravimetric (TGA) analyses. The association constant of the ligand and the stability constants of its complexes were calculated by pH-metric measurements in 50% ethanol–water mixture. Also, DFT method was used to draw the geometry of all compounds and the parameters such as bond lengths, bond angles, dipole moment, Frontier orbitals (HOMO, LUMO), MEP and other energetic parameters (optical energy gap, softness, hardness, electronegativity) were evaluated. The prepared H2NPT reacted with Co2+, Ni2+ and Zn2+ and Cu2+ metal ions to form colored precipitates that were readily floated to the surface solution using oleic acid (HOL) surfactant with vigorous shaking of the flotation cell. The heavy metals' concentrations in the dissolved precipitates are determined by flame atomic absorption spectrometry (FAAS). The different parameters affecting the flotation process were thoroughly investigated, viz. pH of sample solution, concentration of ligand, metal ions and HOL, temperature and interfering ions. Nano-gram quantities of Cu2+, Co2+, Ni2+ and Zn2+in 1500-ml samples are quantitatively determined with 1-Nicotinoyl-4-phenyl thiosemicarbazide (H2NPT) at pH 3.0–6.5 for Cu2+ and at 7.0–7.5 for Co2+, Ni2+ and Zn2+. The concentrations of these heavy metals are increased 300-fold. Interferences, on the flotation process, from various foreign ions were avoided by adding excess H2NPT. The mode of chelation between H2NPT and the investigated metal ions is proposed to be through the S, N and/or O atoms of the ligand. The mechanism of flotation is proposed to be due to an electrostatic interaction between the HOL surfactant and the formed metal–ligand complexes through H-bond formation. The proposed multi-element flotation methodology has been utilized for the determination of the analytes in certified reference materials, alloys, synthetic mixtures and in water samples with a recovery % more than 90% and a relative standard deviation (RSD), as a precision < 2%.

Comparative line position and line strength analysis of the [formula omitted] dyad of [formula omitted] and [formula omitted

A highly accurate ro-vibrational analysis of FTIR spectra (line positions of 13CD4 and line strengths of both the 12CD4 and 13CD4 species) is presented. The high-resolution infrared spectra of both molecules were measured with a Bruker IFS125 HR Fourier transform infrared spectrometer at an optical resolution of 0.003 cm−1 and analyzed in the regions of 800–1400 cm−1 where the ν2/ν4 dyad is located. The number of 901 transitions with Jmax=23 were assigned to the ν4 and ν2 bands of 13CD4 (this number is about 5.3 times higher in comparison with the number of known assigned transitions for 13CD4). The weighted fit of experimental line positions was made using the Hamiltonian model which takes into account the resonance interactions between the (0001,F2) and (0100,E) vibrational states. As a result, set of 18 fitted parameters of the (0001,F2)/(0100,E) vibrational states of 13CD4 was determined which reproduce the initial 901 experimental ro–vibrational line positions with the drms=2.59×10−4 cm−1, which is close to the experimental uncertainty of the recorded spectra and about 1330 times better in comparison with the reproduction of the same line position values by the use of parameters from Loëte et al. (1983). The analysis of 1557 experimental lines of the dyad of 12CD4 and 131 lines of the dyad of 13CD4 was fulfilled with the Hartmann–Tran profile to simulate the measured line shape and to determine experimental line intensities. Sets of 6/1 varied effective dipole moment parameters of 12CD4/13CD4 are determined which reproduce the initial 1557/131 line strengths with the drms=4.80% and 4.21%. Lists of the assigned line positions and strengths in the studied region are presented as the Supplementary data to this paper.

De novo unified robust antidiabetic pharmacophores based on biopotent hybrid material: DFT‐assisted design, optimized molecular structure, and understanding mechanism of antidiabetic bioassay

De novo unified robust antidiabetic pharmacophores based on hybrid material were rationally designed, generated, and characterized by spectroscopic evidences and DFT (B3LYP method). These hybrid pharmacophores demonstrated robust antidiabetic activity. Semicarbazones were used for the generation of these hybrid pharmacophores. Semicarbazones of heterocyclic β‐diketones were synthesized by conventional heating as well by green approach (microwave heating). The results obtained from both the approaches have been summarized and compared. Incorporation of dimethyltin(IV) moiety into some semicarbazones of heterocyclic β‐diketones resulted in the formation of biopotent dimethyltin(IV) formulations of the type Me2SnLA where LH2 = , R = −CH3, L(1)H2, Complex 1; R = −CH2CH3, L(2)H2, Complex 2; R = −C6H5, L(3)H2, Complex 3; and R = p‐ClC6H4−, L(4)H2, Complex 4. One representative semicarbazone of heterocyclic β‐diketone (L(4)H2) and its corresponding dimethyltin(IV) complex Me2SnL(4) (Complex 4) were also studied using computational method (DFT‐B3LYP). Optimized molecular structure, bond lengths, bond angles, EHOMO, ELUMO, dipole moment, polarizability, and other global reactivity parameters were calculated. Energy gap (ΔE) of the ligand L(4)H2 and its corresponding complex has also been compared. Optimized molecular structure–antidiabetic activity relationship of two representative ligands and the corresponding complexes has also been studied. The unified hybrid pharmacophores exhibited robust antidiabetic activity.

Effective Dipole Moment Model for Axially Symmetric C3v Molecules: Application to the Precise Study of Absolute Line Strengths of the ν6 Fundamental of CH335Cl.

The effective dipole moment model for molecules of axial C3v symmetry is derived on the basis of the symmetry properties of a molecule which, on the one hand, is of the same order of efficiency (but much simpler and clearer in applications) as the analogous models derived on the basis of the irreducible tensorial sets theory, and, on the other hand, mathematically more correct in comparison with concepts like the Herman-Walles function used in the models. As an application of the general results obtained, we discuss high-resolution infrared spectra of CH335Cl, recorded with the Zürich prototype ZP2001 (Bruker IFS125 HR) Fourier transform infrared spectrometer at a resolution of 0.001 cm-1 and analyzed in the region of 880-1190 cm-1 (ν6 bending fundamental centered at ν0 = 1018.070790 cm-1). Absolute strengths of more than 2800 transitions (2081 lines) were obtained from the fit of their shapes both with Voigt and Hartmann-Tran profiles, and parameters of the effective dipole moment of the ν6 band were determined by the computer code SYMTOMLIST (SYMmetric TOp Molecules: LIne STrengths), created on the basis of a derived theoretical model. As the first step of the analysis of the experimental data, assignments of the recorded lines were made. A total of 5124 transitions with Jmax = 68, Kmax = 21 were assigned to the ν6 band. The weighted fit of 2077 upper energy values obtained from the experimentally recorded transitions was made with a Hamiltonian which takes into account different types of ro-vibrational effects in doubly degenerate vibrational states of the C3v-symmetric molecule. As the result, a set of 25 fitted parameters was obtained which reproduces the initial 2077 upper "experimental" ro-vibrational energy values with a root mean square deviation drms=4.7×10-5 cm-1. At the second step of the analysis, the computer code SYMTOMLIST was used for determination of the parameters of the derived effective dipole moment model. Six effective dipole moment parameters were obtained from the weighted fit procedure which reproduces absolute experimental strengths of the 2804 initial experimental transitions with a relative drms=3.4%.

Exploration of DFT and TD-DFT computation to investigate the interaction between paracetamol and lithium or its compounds

Paracetamol is a commonly used antipyretic drug and its consumption drastically was increased during the COVID-19 times as fever was one of the symptoms. The excessive usage of paracetamol could harm humans, as the unused accumulated paracetamol can involve in the reaction with many small molecules as well as can interact with several biomolecules. Lithium chloride in its hydrated form is used as an antimanic drug and a geroprotector. It is needed in very small quantities by humans. Tetrahydrated form of lithium ion is the most stable hydrated form. Herein, the authors have investigated the interaction of paracetamol with tetrahydrated lithium chloride (1:1 and 1:2) using the DFT and TD-DFT calculations at 298 K and 310 K. The interaction of paracetamol with lithium chloride P1 (1:1), P2 (2:1), P3 (3:1) and P4 (4:1) are also studied by DFT calculations in default and CPCM model. The authors have calculated the free energy, optimization energy, dipole moment and other thermodynamic parameters of all the systems. Based on enthalpy and change in Gibbs free energy, the interaction was maximum between the paracetamol and tetrahydrated lithium chloride at 298 K as well as 310 K which indicates that the hydrated lithium chloride is being consumed by unused paracetamol. In P1 and P3, lithium showed interaction with oxygen of phenolic group and other atoms of all the paracetamol molecules present, while in P2 and P4, lithium showed these interactions with only one paracetamol molecule.

New acetylene line list near 3.8-µm - Part I

Two acetylene spectra were recorded between 2350 and 2750 cm−1 with Fourier Transform Spectrometer (FTS) using high optical path length. 14 bands were observed for the first time including one cold band. The positions and the intensities of the lines have been measured for 824 transitions of the 12C2H2 isotopologue. The band centers, the band strengths, the upper level spectroscopic constants and the Herman-Wallis parameters were retrieved for all bands. The effective dipole moment parameters of the ΔP = 4 region were refined, P being the polyad number defined as P = 5V1 + 3V2 + 5V3 + V4 + V5, where Vi are the vibrational normal mode principal quantum numbers, with i = 1 − 5. An updated line list for the ∆P = 4 series of transitions is proposed as supplementary data in order to improve the spectroscopic databases such as HITRAN or GEISA.

Investigations of 6-Fluoro-4-Oxo-3,4-Dihydro-2H-Chromene-2-Carboxylic Acid by Quantum Computational, Spectroscopic, TD-DFT with Various Solvents and Molecular Docking Studies

The density functional theory and vibrational spectroscopy investigation were carried out on 6-Fluoro-4-oxo-3,4-dihydro-2H-chromene-2-carboxylic acid (FODHCC). The optimized structure, vibrational frequencies, and other chemical parameters are obtained using the B3LYP method with a 6-311++G(d,p) basis set. FT-IR studies are used to identify the various functional groups, which are then compared with simulated spectra. Atoms In Molecules (AIM) studies are carried out to know the bonding nature. NBO analysis is used to investigate the interactions between donors and acceptors. The stability, hardness, and softness are studied by Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO). The molecular electrostatic potential (MEP) is used to determine the molecule’s reactive regions. The maximum absorption wavelength is determined using the UV-Vis spectrum and compared with the simulated spectrum created using TD-DFT/CAM technique with various solvents. The NLO studies were carried out on the molecule to know the dipole moment and other NLO parameters. The molecule is utilized in biological studies such as molecular docking and drug similarity.

The ν3 band of 16O14N18O: Line positions and intensities

The Fourier transform IR spectra of samples prepared by mixing two gaseous species 18O2/14N16O (1:2) have been recorded in the region of the ν3 band of nitrogen dioxide. The spectra contain the lines corresponding to the ν3 band of the 16O14N18O isotopologue within the 1540–1640 cm−1. In total 1795 lines of the ν3 band of this isotopologue were assigned with the rotational quantum numbers N and Ka up to 51 and 12, respectively, what corresponds to 3487 electron spin-rotation-vibration transitions. The overall measured set of the line positions was used to fit the effective Hamiltonian parameters. The fitted set of the parameters reproduces the observed line positions with an rms of 3.6 × 10−3 cm−1. A selected set of the measured line intensities was used to determine the effective dipole moment parameters describing the line intensities of the ν3 band. The rms deviation of the fit is 5.0%. It was found that the lines with the ΔKa = ±1 are very weak compared to those with the ΔKa =0. At attained sensitivity only few lines with the ΔKa = ±1 were assigned. The measured line intensities lead to the small value of the dipole moment derivatives ratio |(∂μx/∂q3)(∂μz/∂q3)|≈0.139.

Electric double layer theory for room temperature ionic liquids on charged electrodes: Milestones and prospects

In this review, we shortly summarize the basic theoretical milestones achieved in the mean-field theory of room temperature ionic liquids on charged electrodes since the publication of Kornyshev's seminal article in 2007. We pay special attention to the behavior of the differential capacitance profile and the microscopic parameters of ions that can have a substantial influence on it. Among them are parameters of short-range specific interactions, ionic diameters, static polarizabilities, and permanent dipole moments. We also discuss the recent ‘nonlocal’ mean-field theories that can describe the overscreening behavior of the local ionic concentrations, as well as the crossover from overscreening to crowding.

Franck-Condon and Herzberg-Teller Signatures in Molecular Absorption and Emission Spectra.

Some molecules of chemical and biological significance possess vibrations with significant Herzberg-Teller (HT) couplings, which render the Franck-Condon (FC) approximation inadequate and cause the breakdown of the well-known mirror-image symmetry between linear absorption and emission spectra. Using a model two-state system with displaced harmonic potential surfaces, we show analytically that the FC-HT interference gives rise to asymmetric intensity modification, which has the same sign for all transitions on one side of the 0-0 absorption line and the opposite sign in the equivalent fluorescence transitions, while the trend is exactly reversed for all transitions on the other side the 0-0 line. We examine the dependence of the absorption-emission asymmetry on the mode frequency, Huang-Rhys factor, and dipole moment parameters to show the recovery of symmetry with particular combinations of parameters and a crossover from fluorescence to absorption dominance. We illustrate the analytical predictions through numerically exact calculations in models of one and two discrete vibrational modes and in the presence of a harmonic dissipative bath. In addition to homogeneous broadening effects, we identify large asymmetric shifts of absorption and emission band maxima, which can produce the illusion of unequal frequencies in the ground and excited potential surfaces as well as a nontrivial modulation of spectral asymmetry by temperature, which results from the enhancement of transitions on one side of the 0-0 line. These findings will aid the interpretation of experimental spectra in HT-active molecular systems.

Experimental spectra, electronic energies (liquid and gaseous phases) quantum computational strategies and potential biological activity studies of (1E, 4E)-1, 5-bis (4-methoxyphenyl) penta-1,4-dien-3-one: An antiviral agent

In this work, molecular structure, electronic solvation, and wave functional studies are investigated. Spectroscopic FT-IR and FT-Raman spectra of (1E, 4E)-1,5-bis(4-methoxyphenyl) penta-1,4-dien-3-one (MPPD) compound are investigated, analyzed experimentally and by using DFT tools (Gaussian 09). The geometrical structure was optimized and the vibrational wavenumbers of the MPPD compound are calculated and compared with experimental results. Electron depletion regions are identified from wave functional study (ELF). Charge transfer properties are explored from UV–Vis spectral analysis using DMSO solvent. The nucleophilic sites are identified from MEP and Fukui functions analysis. Electronic band gap energies are computed with different solvent molecules. The dipole moment parameter is computed to explain the NLO behavior of the MPPD compound. Intramolecular interactions are explained by the NBO method. A molecular docking study is performed with a viral protein.

Effects of Solvent and Electrospinning Parameters on the Morphology and Piezoelectric Properties of PVDF Nanofibrous Membrane.

PVDF electrospun membranes were prepared by employing different mixtures of solvents and diverse electrospinning parameters. A comprehensive investigation was carried out, including morphology, nanofiber diameter, crystallinity, β-phase fraction, and piezoelectric response under external mechanical strain. It was demonstrated that by using low-toxicity DMSO as the solvent, PVDF membranes with good morphology (bead-free, smooth surface, and uniform nanofiber) can be obtained. All the fabricated membranes showed crystallinity and β-phase fraction above 48% and 80%, respectively; therefore, electrospinning is a good method for preparing PVDF membranes with the piezoelectric properties. Moreover, we considered a potential effect of the solvent properties and the electrospinning parameters on the final piezoelectric properties. When PVDF membranes with different β-phase fractions and crystallinity values are applied to make the piezoelectric transducers, various piezoelectric voltage outputs can be obtained. This paper provides an effective and efficient strategy for regulating the piezoelectric properties of PVDF electrospun membranes by controlling both solvent dipole moment and process parameters. To the best of our knowledge, this is the first time that the influence of a solvent’s dipole moment on the piezoelectric properties of electrospun materials has been reported.

Hydrogen adsorption and storage on palladium-functionalized C20 bowl and C20H10 bowl molecule including hydrogen saturation

This study investigated hydrogen molecule adsorbing on palladium-functionalized C20 bowl and its H-saturated form (C20H10 bowl) using the B3LYP-D3 model. Moreover, this study examined the stability of different isomers of hydrogen adsorption. The values of adsorption energy were calculated in the investigated systems. This study demonstrated changes in the dipole moment and structural parameters. Additionally, this study indicated the differences in the frontier orbital energy and HOMO—LUMO gap values. Electrophilicity-based charge transfer showed charge transfer between fragments. Furthermore, this study also computed the hydrogen molecule's recovery duration in the investigated systems. In addition, the present study showed the field emission features of the examined system.

Promising bio-active complexes of platinum(II) and palladium(II) derived from heterocyclic thiourea: Synthesis, characterization, DFT, molecular docking, and anti-cancer studies

Four Platinum(II) and Palladium(II) heterocyclic thiourea complexes have been prepared; [Pt(CPPT)2](1), [Pd(CPPT)2](2), [Pt(MPPT)2](3), and [Pd(MPPT)2](4) (Where HCPPT=1-(5-chloropyridin-2-yl)-3-phenylthiourea, HMPPT=1-(3-methylpyridin-2-yl)-3-phenylthiourea). Both the ligands and the complexes were characterized by different spectroscopic techniques including: FT-IR, 1H, 13C-{1H} NMR and Mass spectroscopy. The spectroscopic data analysis suggested that the complexes (1–4) adopt a square planar geometry with cis-configuration of platinum and trans- configuration of Palladium complexes. Antiproliferative data indicated that palladium(II) complexes exerted a potent cytotoxic activity in comparison with platinum(II) complexes. Among all tested complexes, [Pd(MPPT)2] exhibited a promising activity with an IC50 value of 10.44 and 17.7 µM against colon cancer cell lines (LoVo) and breast cancer cell lines (MCF-7) respectively. Theoretical calculations were applied to estimate the physical properties and the inhibition activity of cancer cells by docking. Gaussian 09 software with 6-311G (d, p) basis set was used for theoretical study. Furthermore, quantum chemical parameters of highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), dipole moment, energy gap and other parameters were used to evaluate the complexes activity. MGL tools and DSV software were used to test the complexes inhibitions of breast cancer by blocking the damage cells.