Fukui Function Analysis Research Articles

Spectroscopic characterization, DFT studies, molecular docking and cytotoxic evaluation of 4-nitro-indole-3-carboxaldehyde: A potent lung cancer agent.

The 4-nitro-1H-indole-carboxaldehyde (NICA) molecule was characterized experimentally using FT-IR, FT-Raman and UV-Vis spectra, and it was studied theoretically using DFT calculations. The optimized structure of the NICA molecule was determined by DFT calculations using B3LYP functional with cc-pVTZ basis set. The electron localization function (ELF) and local orbital localizer (LOL) studies were performed to visualize the electron delocalization in the molecule. The experimental and theoretical wavenumbers of the title molecule were assigned using VEDA 4.0 program. The charge delocalization and stability of the title molecule were investigated using natural bond orbital (NBO) analysis. Frontier molecular orbitals (FMOs) and related molecular properties were calculated. UV-Vis spectrum was calculated theoretically and validated experimentally. The reactive sites of the molecule were studied from the MEP surface and Fukui function analysis. The molecular docking analysis reveals that the NICA ligand shows better inhibitory activity against RAS, which causes lung cancer. The in vitro cytotoxic activity of the molecule against human lung cancer cell lines (A549) was determined by MTT assay. Thus, the NICA molecule can be used as a potential candidate for the development of the drug against lung cancer.

Geometries, Reactivity and Binding Energy of Urea on Mg9O9

In this paper we present global and local reactivity results of the urea gas phase molecule and gas phase (MgO)18 agglomerated for understand charge distribution and binding energy (MgO)-UREA. We analyze the quantum chemical descriptors, ionization potential (I), electron affinity (A), chemical hardness (ɳ), chemical potential (μ) and Global Philicity Index (ω) and site reactivity or site selectivity condensed Fukui function analysis of the distribution of atomic charges investigated with methods of Mulliken, Merz-Kolman and Natural Atomic Charges. For instance, the binding energies of MgO-Urea systems are.

Vibrational spectral, density functional theory and molecular docking analysis on 4-nitrobenzohydrazide

To understand the structural behavior of C-nitro compound 4-nitrobenzohydrazide (4NBH), a detailed spectroscopic study has been taken up. Spectral analyses of 4NBH molecule have been experimentally investigated in solid phase by FT-IR, FT-Raman, UV–visible and NMR techniques. The molecular structure has been optimized by using the B3LYP/6–311++G (d,p) calculations. Normal co-ordinate analysis (NCA) has been carried out to perform comprehensive vibrational spectral assignments. Natural bond orbital analysis (NBO) explains the stability and different types of hydrogen bonds with in the molecule. UV–Vis spectrum helps to found the band gap energy of 4NBH molecule and the electronic properties are computed with TD-DFT method. The 1H and 13C NMR chemical shifts are recorded and analyzed. The interpreted HOMO and LUMO energies indicate the chemical stability of the molecule. The chemical reactivity sites have been revealed by fukui function and molecular electrostatic potential (MEP) analysis. Docking studies have been conducted to predict 4NBH anti-tubercular activity against four transaminase-Bio A type PDB's. In-vitro analyses have been performed with fungal and bacterial pathogens Aspergillus niger and E.Coli.

Spectroscopic and molecular docking studies on 1-Hydroxyanthraquinone: A potent ovarian cancer drug

In the present study, the structural and spectroscopic investigations of1-Hydroxyanthraquinone molecule were performed using density functional theory quantum chemical calculations and validated by experimentally. In addition, the inhibitory nature of the title molecule was evaluated using molecular docking analysis. The potential energy surface scan was performed and the most stable molecular structure of the molecule was predicted. The molecular structure of the molecule was optimized and the harmonic vibrational wavenumbers of the molecule were calculated. The vibrational wavenumbers were also observed using FT-IR and FT-Raman spectra of the molecule. The calculated and observed vibrational wavenumbers were assigned. The 13C NMR isotropic chemical shift values of the molecule were calculated in DMSO solution and compared with the experimental data. The UV–Vis absorption spectrum of the molecule was computed in liquid phase (ethanol) and compared with the observed spectrum. Frontier molecular orbitals analysis reveals the molecular reactivity and kinetic stability of the molecule. The Mulliken atomic charge distribution, Fukui function and molecular electrostatic potential surface analysis of the molecule validate the reactive nature of the HAQ molecule. The natural bond orbital analysis indicates that the title molecule is bioactive in nature. The molecular docking analysis confirms that the title molecule acts as a good inhibitor of cyclooxygenase-1 protein than other selected proteins, which is overexpressed in some ovarian cancer cells. Hence, the present study paves the way for designing the novel drugs for the treatment of ovarian cancer.

Recognition of Fe3+ by a new azine-based fluorescent “turn-off” chemosensor and its binding mode analysis using DFT

A highly responsible Fe3+, azine chemosensor (EBHMM) was successfully designed and synthesized. The structure of the synthesized azine was confirmed by FT-IR, UV–Vis, 1H and 13C{1H} NMR spectroscopic techniques and high resolution mass spectrometry. The azine shows sensitive and selective fluorescence “turn-off” towards Fe3+ ion over other metal ions in 1:1 DMF-H2O (5 μM, pH = 7.4) solution. The fluorescence quenching on the addition of Fe3+ ion at various pH clearly indicate that the azine can be used for the quantitative determination of Fe3+. The binding of Fe3+ with chemosensor was analyzed by confirming the formation of metal-ligand complex using HRMS-ESI spectrometry. The binding stoichiometry (1:1) was calculated using Stern-Volmer method and the binding constant 1.0034 M-1 was calculated using Benesi-Hildebrand plot. The exact binding sites of the chemosensor with Fe3+ ion is theoretically explained with Fukui Function using DFT study in B3LYP function with B3LYP/6-311++G (d,p) level of basis set. The “turn-off” fluorescence through photo induced electron transfer (PET) process is discussed and confirmed with the results of Fukui Function and Frontier molecular orbital analysis.

Computational Study of Novel 2,3-Bis[(1-methyl-1H-imidazole-2-yl)sulfanyl]quinoxaline: Structural Aspects, Spectroscopic Investigation, HOMO-LUMO, MESP, NLO, ADMET Predictions and Molecular Docking Studies as Potential Biotin Carboxylase and Antibiotics Resistant Aminoglycoside Phosphotransferase APH(2")IVA Enzyme Inhibitor

In this paper, a complete quantum chemical calculation has been done to describe the relevant structural aspects of novel 2,3-bis[(1-methyl-1H-imidazole-2-yl)sulfanyl]quinoxaline with combination of DFT/B3LYP method 6-311++G(d,p) basis set in gas phase and in solvent phase. The molecular structure was examined by using IR, 1H & 13C NMR and UV-visible techniques and solvent effect on spectroscopic properties are also discussed. The vibrational assignments are analyzed by PED using Gauss View 5.0 and VEDA 4.0 program. The 1H NMR and 13C NMR chemical shifts are calculated using the gauge-independent atomic orbital method (GIAO method) in gas phase and in solvents (water, DMSO and chloroform). The UV spectrum is calculated by using TD-DFT/6-311++G(d,p) method in gas phase and in solvent (water, DMSO and chloroform) using IEF-PCM model. With the help of theoretical calculations chemical activities, electrophilic/nucleophilic nature and sites in the molecule, molecular and chemical properties that cannot be obtained by experimental way are obtained. Accordingly, molecular electrostatic potential (MESP), hardness (η)/softness (S) parameters, net charges analyses are investigated to gain electrophilic and nucleophilic nature. Also the sites in molecule and Fukui function analysis are discussed. The dipole moment (μ), polarizability (αtot), anisotropic polarizability (Δα) and first-order hyperpolarizability (βtot) of the title compound are reported and results shows that the material is capable to generate non-linear effect (NLO). The in silico study of all th e biological and ADMET properties of title molecule are also discussed and compared with reference drug ciprofloxacin antibiotics. The title molecule and reference drug ciprofloxacin docked with biotin carboxylase enzyme (PDB ID: 2V59) of E. coli and aminoglycoside phosphotransferase APH(2")IVA (PDB ID: 4DFU) of Enterococcus casseliflavus receptor with the help of Molegro molecular viewer 2.5 program and binding affinity (ΔG) were determined by ParDock server.

Computational Design, Spectral, NBO, DOS, Bioactivity Evaluation, ADMET Analysis, Third-Order non-linear Optical and Quantum Chemical Investigations on Hydrogen Bonded Novel Organic Molecular Complex of 4-[Bis[2-(acetyloxy)ethyl]amino]benzaldehyde (4B2AEAB) Derivatives for Opto-Electronic Applications

In this paper, the authors reported a theoretical investigation on molecular structure, geometry optimization, global and local chemical reactivity descriptors calculations, NBO study, DOS, non-linear optical behaviour and vibrational wavenumbers of the novel 4-[bis[2- (acetyloxy)ethyl]amino]benzaldehyde (4B2AEAB) were carried out by DFT (B3LYP and B3PW91) methods with 6-31+G (d, p) basis set in water solvent. The calculated vibrational wavenumbers are found to be in good agreement with experimental FT-IR spectra and PED analysis using GaussView 5.0 and VEDA 4 program. The UV-Vis absorption spectrum of 4B2AEAB was calculated by using TD-DFT/B3LYP/6-31+G(d,p) in gas phase, water, CHCl3, DMSO and CH2Cl2 solvents using CPCM model and λmax in range of 354.16, 341.35, 343.74, 342.18 and 342.64 nm, respectively. The density of state (DOS spectrum) of the compound in term of HOMOs and LUMOs and MESP were calculated and analyzed. The temperature effects on the thermodynamic properties are also discussed. The calculated 1H NMR and 13C NMR chemical shift using GIAO method and solvent effect are investigated by B3LYP/6-31+G(d,p) in gas phase, chloroform, water, DMSO and CH2Cl2 solvents and correlate with experimental chemical shifts. The dipole moment, polarizability and the first static hyperpolarizability values show that the 4B2AEAB molecule is active non-linear optical (NLO) material. The nucleophilic and electrophilic reactive sites in the 4B2AEAB and its derivatives were analyzed by Fukui function analysis using Mulliken charge. The charge transfer, conjugative interactions and delocalization of electron density are analyzed by natural bond orbital (NBO) analysis. The biological properties and ADMET study of 4B2AEAB and its derivatives are also discussed.

Regioselective oxidation of tetracycline by permanganate through alternating susceptible moiety and increasing electron donating ability

Permanganate has attracted much attention in wide range of chemistry and particularly in degradation of environmental pollutants. However, few studies have discussed the feature of regioselective reactivity of permanganate with specific moiety of the target compound. Herein, we studied the reaction between permanganate and tetracycline that is an emerging micropollutant with different species containing several electron-rich groups. The second-order rate constants increased from 6.0 to 9.0 and could be quantitatively modeled by considering the speciation of both reactants, yielding kTC0 = 11.7 (mol/L)−1 sec−1, kTC− = 35.7 (mol/L)−1 sec−1, kTC2− = 43.1 (mol/L)−1 sec−1 for individual reaction channels. Degradation products were then identified as the hydroxylated and demethylated compounds. The result suggested a rate-limiting step of simple hydroxylation at the phenolic and/or alkene moieties, while the demethylation should be caused by the unavoidably formed manganese oxide via single electron oxidation. This is supported by the DFT calculation, indicating the primary oxidation of phenolic group of TC0 with activation barrier of 44.5 kcal/mol and of alkene group of TC− and TC2− with activation barriers of 44.0 and 43.4 kcal/mol, respectively. This is in agreement with the experimental results, implying the alternation of regioselectivity associated with the deprotonation process. The result was further supported by performing the Fukui function and electrostatic potential analysis, reflecting the more probable site and better electron donating tendency beneficial to the permanganate oxidation.

Spectroscopic, quantum chemical, molecular docking and in vitro anticancer activity studies on 5-Methoxyindole-3-carboxaldehyde

The FT-IR and FT-Raman spectra of 5-Methoxyindole-3-carboxaldehyde (MICA) molecule were recorded. The experimental and theoretical vibrational wavenumbers were assigned and compared. The non-linear optical (NLO) activity of the molecule was confirmed using second harmonic generation test and compared with theoretical result. The natural bond orbital (NBO) analysis was carried out to evaluate the intramolecular stabilization interactions of the molecule, which are responsible for the bio-activity of the molecule. The molecular electrostatic potential surface, frontier molecular orbitals and Fukui function analysis reveal the charge transfer interactions in the molecule. The total density of states (TDOS), partial density of states (PDOS), and overlap population density of states (OPDOS) studies were performed in order to visualize the molecular orbital contributions of the molecule. The molecular docking analysis was carried out to explore the inhibitory nature of the molecule, which indicates that molecule can acts as a novel inhibitor of lung cancer causing VEGF receptor. In addition, the in vitro cytotoxicity of the molecule confirms the anticancer activity against the human pulmonary epithelial lung cancer cell lines (A549). Hence, the present investigations pave the way for the development of lung cancer drugs.

Spectroscopic (FT-IR, FT-Raman, NMR and UV-Vis), ELF, LOL, NBO, and Fukui function investigations on (5-bromo-benzofuran-3-yl)-acetic acid hydrazide (5BBAH): Experimental and theoretical approach

Experimental and theoretical spectroscopic studies were performed for the (5-Bromo-benzofuran-3-yl)-acetic acid hydrazide (5BBAH) molecule. The research work was performed in two levels. In the first level, experimental FT-IR, FT-Raman, NMR (1H, 13C) chemical shift and UV-Vis spectral data were recorded. In the next level the theoretical computations have been conducted from DFT/B3LYP/6-311++G (d, p) basis level. Initially, the theoretical geometrical parameters were obtained and matched with related experimental parameters. The computed FT-IR and FT-Raman frequencies were collected from same basis level and matched with experimental data. The vibrational assignments were achieved on the PED of individual vibrational modes. The theoretical NMR chemical shifts were compared with recorded experimental data. Theoretical (TD-DFT) and experimental UV-Vis absorption wavelengths (λ) were compared with each other. In addition, FMO, NBO, MEP, ELF, LOL and Fukui function analysis were performed.

Quantum chemical, experimental, theoretical spectral (FT-IR and NMR) studies and molecular docking investigation of 4,8,9,10-tetraaryl-1,3-diazaadamantan-6-ones

The compounds 4,8,9,10-tetraaryl-1,3-diazaadamantan-6-ones (a–e) were synthesized and characterized by FT-IR, 1H and 13C NMR spectra, and the spectral data have been theoretically analyzed by the DFT method. The electronic properties including a highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) and related parameters were calculated with B3LYP/6-311 G (d, p) basis set. The observed HOMO and LUMO mappings describe the different charge transfer possibilities within the molecule. Besides, the reactive properties of the molecules have been addressed based on the frontier molecular orbital analysis. The Molecular Electrostatic Potential and Fukui function analysis reveal the sites for electrophilic attack and nucleophilic reactions in the molecule. The intramolecular contacts have been interpreted using Natural Bond Orbital analysis and the thermodynamic properties also presented. The molecular docking study has been executed to study the binding interactions of the synthesized compounds with H1N1 swine virus-M2 proton channel and COX-2 protein.

Spectroscopic (Ft-Ir, Nmr, Uv-Vis, Fluorescence) and Dft Studies (Molecular Structure, Ir and Nmr Spectral Assignments, Nbo and Fukui Function) of Schiff Bases Derived from 2-Chloro-3-Quinolinecarboxaldehyde

Two Schiff bases are newly prepared by the condensation of 2-chloro-3-quinolinecarboxaldehyde with ethylenediamine and 1,4-butanediamine. The Schiff bases are characterized by the elemental analysis, IR, 1H and 13CNMR, UV-Vis, and fluorescence spectroscopies. Structural parameters together with the theoretical assignment of their vibrational frequencies and NMR chemical shifts are determined using density functional theory (DFT) approaches. There is good consistency between the DFT-calculated results and the experimental data, confirming the validity of the optimized geometries for the investigated Schiff bases. Optimized geometries of two Schiff bases are not planar, however, the substitutions are essentially in the same plane with the pyridine rings. Shapes of the frontier orbitals are determined using the natural bond orbital (NBO) analysis. Due to a high energy gap between the frontier orbitals, both Schiff bases are stable. Based on the Fukui function analysis, two Cl atoms and two azomethine nitrogen atoms are four suitable donor atoms for coordination to metal ions. Effects of the temperature and pH on the UV-Vis absorbance and fluorescence intensity of the Schiff bases are studied in a DMSO solution.

Diaquabis(5-methoxyindole-2-carboxylato)bis(3-picoline)nickel(II) Complex: Synthesis, Characterization, XRD, TGA, DFT and HSA

A new complex of diaquabis(5-methoxyindole-2-carboxylato)bis(3-picoline)nickel(II) (Ni(5-MeOI2CA)2(3-pic)2(H2O)2), was synthesized for the first time and characterized by elemental analysis, FT-IR and electronic spectroscopy (UV-Vis) and single-crystal X-ray diffraction (XRD) techniques. The thermal degradation of the Ni(II) complex was investigated using thermogravimetric and differential thermal analyses techniques in oxygen atmosphere. The molecular structure of the complex was determined by single crystal X-ray diffraction technique. Hirshfeld surface analysis (HSA) investigated the packing modes and intermolecular interactions in molecular crystals, as they provide a visual picture of intermolecular interactions. In addition, all computational studies at B3LYP/6-311++G(d,p) were carried out for theoretical characterization of Ni(II) complex. The optimized geometry results, which were well represented the X-ray data, were shown that the chosen of DFT/B3LYP/6-311++G(d,p) was a successful choice for title compound. After a successful optimization, FMOs, chemical activity, non-linear optical properties (NLO), molecular electrostatic potential (MEP), Mulliken population (MPA), natural population analyses (NPA), Fukui function analysis (FFA) and natural bond orbital analysis (NBO), which could not obtained by experimental ways, were calculated and investigated. The computed of net charges and chemical activity studies which helped to identifying the electrophilic/nucleophilic nature.

4-(2-Methoxy-4-(prop-1-enyl)phenoxy)phthalonitrile; synthesis, characterization, Hirshfeld surface analysis and chemical activity studies

This work deals with experimental and theoretical study of the 4-(2-methoxy-4-(prop-1-enyl)phenoxy)phthalonitrile (MPPP). The MPPP was synthesized and characterized by FT-IR and NMR, and X-ray single-crystal determination. Hirshfeld surface analysis revealed the nature of intermolecular contacts, the fingerprint plots and molecular surface contours provided the information about the percentage contribution and bond interactions. The structural data of the molecule in the ground state was calculated using the DFT employing B3LYP/6-311++G(d,p) basis set. The energetic behavior of the organic dye sensitizer MPPP in solvent media was examined. In addition, chemical activity, NLO, net charges by MPA & NPA, MEP and Fukui function analysis were investigated. Based on vibrational analysis, the thermodynamic properties were calculated at different temperatures and corresponding relations between the properties and temperature were obtained.

Experimental and computational chemistry studies on the removal of methylene blue and malachite green dyes from aqueous solution by neem (Azadirachta indica) leaves

ABSTRACTAdsorption of methylene blue and malachite green dyes from aqueous solution by neem leaves was studied using experimental and computational chemistry approaches. The two dyes have N–H stretch, C≡C vibration vibration, C=C stretch and C–Cl stretch as common functional groups. Batch adsorption experiments were concluded by measuring absorbance (at wavelength of maximum absorption, i.e. 660 and 630 nm for methylene blue and malachite green dyes, respectively). The adsorption of the dyes on neem leaves favoured Langmuir and Temkin isotherms and was influenced by concentration, biomass dose, pH and by contact time, and favoured chemisorption mechanism. Although surface adsorption and intra particle diffusion were identified as the rate-limiting steps, a pseudo second-order kinetics was also favoured. Quantum chemical analysis supported better adsorption of methylene blue dye on neem seed surface than malachite green dye and through Fukui function analysis, the site for adsorption of the dyes was proposed.

XRD, FT–IR and UV characterization, hirshfeld surface analysis and local-global chemical descriptor studies of (E)-2-((3-fluorophenylimino)methyl)-3-methoxyphenol (1) and (E)-2-((2-fluorophenylimino)methyl)-3-methoxyphenol (2)

A series of novel (E)-2-((3-fluorophenylimino)methyl)-3-methoxyphenol (1) and (E)-2-((2-fluorophenylimino)methyl)-3-methoxyphenol (2) were synthesized and characterized by X-ray diffraction method, FT–IR and UV–Vis techniques. The experimental FI-IR and UV–Vis spectra showed that 1 and 2 were formed single crystal and displayed enol-imine form. Hirshfeld surface analysis was carried out for title molecules, which reveals the nature of intermolecular contacts, the fingerprint plots and molecular surface contours (dnorm, di and de). The optimized molecular geometry (bond length, bond angle, torsion angle) and all other theoretical computations were calculated by using density functional theory (DFT) B3LYP method with the help of 6-31G (d,p) basis set. The optimized geometry results, which were well represented by the X-ray data, show that DFT/B3LYP 6-31G (d,p) was a suitable level of theory. After a successful optimization, frontier molecular orbitals, chemical activity, non-linear optical properties (NLO), natural bond orbital (NBO) analysis, molecular electrostatic potential (MEP), fukui function analysis, Mulliken population method (MPA) and natural population analysis (NPA), which cannot be obtained experimentally, were calculated and investigated.

Controlled Synthesis of C70 Equatorial Multiadducts with Mixed Addends from an Equatorial Diadduct: Evidence for an Electrophilic Carbanion.

Controlled synthesis of the equatorial tetra-, hexa-, and octaorgano[70]fullerenes with mixed addends was achieved via the reaction of equatorial 7,23-Bn2C70 with MeO- and ArCH2Br. The products were structurally characterized by single crystal X-ray diffraction. The regioselectivity of the reaction was studied by in situ vis-NIR and Fukui function analysis. A surprising electrophilic triorgano[70]fullerene carbanion was shown, and an enhanced fluorescence was observed for the mixed octaadducts.

Mechanochemical formation of chlorinated phenoxy radicals and their roles in the remediation of hexachlorobenzene contaminated soil

Mechanochemical degradation (MCD) is a promising eco-friendly method to dispose persistent organic pollutants (POPs). Mechanically induced free-radical attack was thought to be one of the key elements in initiating and accelerating the dechlorination and degradation of POPs. In this study, mechanochemical formation of free-radicals and their roles in the remediation of hexachlorobenzene (HCB) contaminated soil were explored using both of experimental analysis and quantum chemical calculations. It was found that chlorinated phenoxy radicals(CB-O) can be produced in the milling process and they played a vital role in the dechlorination of HCB, based on the results of electron spin-resonance (ESR) and X-ray photoelectron spectra (XPS). Two transition states of mechanochemical reaction along the formation of pentachlorinated phenoxy radical (PeCB-O) were located, with the energy barriers of 39.4 and 3.4 kJ/mol. The localized orbital locator (LOL), Mayer bond order and topological analysis were also implemented to depict the process in detail. Free-radical attack dominated dechlorination pathway of HCB in the MCD process was also verified by the Fukui function analysis. The study on the mechanically-induced generation of free-radicals and their associated modes of action on the degradation of HCB will provide a deep insight into mechanochemical remediation mechanism of POPs contaminated soil.

X-ray structure determination, Hirshfeld surface analysis, spectroscopic (FT-IR, NMR, UV–Vis, fluorescence), non-linear optical properties, Fukui function and chemical activity of 4′-(2,4-dimethoxyphenyl)-2,2′:6′,2″-terpyridine

The compound 4′-(2,4-dimethoxyphenyl)-2,2′:6′,2″-terpyridine (Mtpyr) was synthesized and investigated using X-ray single crystal structure determination, combined with Hirshfeld topology analysis of the molecular packing. In addition, Mtpyr was characterized by experimental and theoretical FT-IR, UV–Vis, 1H NMR, 13C NMR and fluorescence emission spectra. The optimized molecular geometry (bond length, bond angle, torsion angle), the complete vibrational frequency and all other theoretical computations were calculated by using density functional theory (DFT) B3LYP method with the help of 6–311++G(d,p) basis set. From the recorded UV–Vis spectrum, the electronic properties such as excitation energies, wavelength and oscillator strength are evaluated by TD-DFT in chloroform solution. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge-independent atomic orbital (GIAO) method and compared with experimental results. The calculated HOMO-LUMO band gap energies confirmed that charge transfer and chemical stability within the molecule. The hyperconjugative interaction energy E(2) and electron densities of donor (i) and acceptor (j) bonds were calculated using natural bond orbital (NBO) analysis. Besides Mulliken and natural population charges (NPA), non-linear optic properties (NLO), Fukui Function analysis, molecular electrostatic potential (MEP) were also computed which helps to identifying the electrophilic/nucleophilic nature.

A comparison of typical additives for copper electroplating based on theoretical computation

Electronic parameters of four additives for copper electroplating including accelerators, mercaptopropane sulfonic acid (MPS) and bis-(acid-sulfopropyl)-disulfide (SPS), inhibitor polyethylene glycol (PEG)and leveler Janus Green B (JGB). They were computed by using DFT/B3LYP method based on the 6-311G + (d, p) basis set. The quantum chemical parameters, which were most relevant to the interaction between the additives and copper surface, were calculated in the gas and aqueous phases for comparison. The condensed Fukui function analysis, molecular electrostatic potential plots and the average local ionization energy plots were applied to predict the most active site(s) of those molecules. Molecular dynamic simulations were also employed to examine the adsorption energies and the adsorption configurations of these additives on Cu (1 1 1) surface under the water environment at 298 K and 323 K conditions. As a result, compared with the other additives in copper electroplating, the unsaturated functional group is an essential factor to levelers. Hence, we predict a novel additive structure according to our calculation results.