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The current investigation, interaction of Cr(CO)3 fragment with corannulene was examined at the B3LYP*/6-311G(d,p) level of theory. C-PCM study of the formed Cr(CO)3(η6- corannulene) complex was reported. Independent and dependent-frequency isotropic polariazability and first hyperpolarizability values of this complex were calculated. The solvent effect on these data were examined using conductor polarizable continuum model (C-PCM). Correlations of the energetics, electronic and optical properties with modified-Buckingham function (Fmodified-Buckingham) were illustrated. Reduced density gradient (RDG) was employed to analyze the interaction between Cr(CO)3 fragment with corannulene. [ABSTRACT FROM AUTHOR]

Electronic, structural, and optical properties of Fe(CO)4[X12Y12] (X = B or Al, Y = N or P) complexes have been illustrated at the mPW1PW91/6-311G(d,p) level of theory. Two possible isomers of the interaction between [X12Y12] nano-cluster and Fe(CO)4 have been considered. In isomer I, Fe(CO)4 fragment interacts with common X–Y bond between six-membered rings. In isomer II, this fragment interacts with common X–Y bond between six-membered and four-membered of cage. Dipole moment values, polarizability parameters, and non-linear optical properties of these complexes have been investigated. Energy decomposition analysis (EDA) has been employed to explore the interactions between nano-cluster and Fe(CO)4. Charge transfer between [X12Y12] nano-clusters and Fe(CO)4 fragment has been explored with electrophilicity-based charge transfer (ECT). QTAIM computations have been employed for illustration the characterizations of Fe–C, Fe–X, and Fe–Y bonds in the studied complexes. In addition, Laplacian bond orders (LBO) of the Fe–C, Fe–X, and Fe–Y bonds have been calculated. Independent gradient model (IGM) based on promolecular density has been used to evaluate the interaction between Fe(CO)4 and [X12Y12]. [ABSTRACT FROM AUTHOR]

The crystal structures of two single-enantiomer compounds, i.e. diphenyl [(R)-(+)-α-ethylbenzylamido]phosphate, C21H22NO3P or (C6H5O)2P(O)[NH-(R)-(+)CH(C2H5)(C6H5)] (I), and N-[(R)-(+)-α-ethylbenzyl]-P,P-diphenylphosphinic amide, C21H22NOP or (C6H5)2P(O)[NH-R-(+)CH(C2H5)(C6H5)] (II), were studied. The different environments at the phosphorus atoms, (O)2P(O)(N) and (C)2P(O)(N), allow the P O/P--N bond strengths to be compared, as well as the N--H...O P hydrogen-bond strengths, and P O/N--H vibrations. The following characteristics related to diastereotopic C6H5O/C6H5 groups in I/II were considered: geometry parameters, contributions to the crystal packing, solution 13C/¹H NMR chemical shifts, conformations, and NMR coupling constants. The phosphorus-carbon coupling constants nJPC (n = 2 and 3) in I and mJPC (m = 1, 2, 3 and 4) in II were evaluated. For a comparative study, chiral analogous structures were retrieved from the Cambridge Structural Database (CSD) and their geometries and conformations are discussed. [ABSTRACT FROM AUTHOR]

In this work, we reported a computational investigation on the interaction between a cycloplatinated thiosemicarbazone (CT) as antiparasitic and antitumor agents with C20 molecule. The solvent impacts were considered by the SCRF based on PCM. The relationships of solvation energies, interaction energy, dipole moment, and N-H stretching frequencies (ν(NH)) values with modified-Buckingham function were illustrated. ETS-NOCV, CDA, and EDA results provided valuable understanding into the interaction between two fragments. [ABSTRACT FROM AUTHOR]

In this work, hollow Poly(aniline-co-pyrrole) (HAP) nanoparticles were synthesized and utilized accompanied by chitosan (CH) to prepare the novel HAP-CH support for metal nanoparticles. ZnFe2O4 (ZFO) nanoparticles were synthesized and incorporated on HAP-CH support to enhance the catalytic activity of Pt nanoparticles in the novel Pt-ZFO/HAP-CH nanocatalyst for methanol electro-oxidation. The prepared catalysts were characterized by Transmission electron microscopy images, Fourier-transform infrared spectroscopy, energy dispersive X-ray, and X-ray powder diffraction analysis. The electrocatalytic performance of Pt-ZFO/HAP-CH nanocatalyst was assessed towards methanol electro-oxidation by some electrochemical techniques including electrochemical impedance spectroscopy, chronoamperometry, and cyclic voltammetry, and compared with that of Pt/HAP-CH. Electrochemical results illustrated that Pt-ZFO/HAP-CH nanocatalyst has higher electrocatalytic activity and durability than that of the Pt/HAP-CH, which is owing to the higher electrochemically active surface area, higher mass activity, better durability, and lower charge transfers resistance. The superior catalytic performance of Pt-ZFO/HAP-CH nanocatalyst reveals that it can be a promising catalyst for developing direct methanol fuel cells (DMFCs). [ABSTRACT FROM AUTHOR]

The iron-based catalysts were prepared via wet-impregnation method. The composition of the final iron catalysts, regarding to the weight ratio is as follow 14%Fe/γ-Al2O3, 14%Fe/3%Cu/γ-Al2O3, 14%Fe/3%Sn/γ-Al2O3 and 14%Fe/3%Cu/1%Sn/γ-Al2O3. The catalysts were characterized using XRD, ICP, BET, H2-TPR, FE-SEM and EDX techniques. The catalytic activity was evaluated in a fixed bed reactor under 2.0 MPa of pressure, H2 : CO = 1 : 1, GHSV = 2 L h–1 , in the temperature range of 270–300°C. Then, the effect of temperature and promoters (Cu and Sn) on the catalyst performance was investigated. CO conversion and product selectivity were also calculated using the results of GC. The results showed that the Cu and Sn promoters increased the reduction rate of Fe2O3 by providing H2 dissociation sites. Higher temperatures were also shown to change the CO conversion and product selectivity. The selectivity of both methane and C2–C4 hydrocarbons decreased while the selectivity of C5+ increased because of simultaneous use of Cu and Sn for promoting iron catalyst. Sn promoter increased FT and WGS activities. [ABSTRACT FROM AUTHOR]

Cu–Fe catalysts incorporated with different amounts of Ca and Mn promoters were prepared using a wet-impregnation method and applied in the Fischer–Tropsch synthesis reaction. The composition of the final iron catalysts in terms of the weight percentage was as follows: 14Fe/3Cu/2Ca/γ-Al2O3, 14Fe/3Cu/2Mn/γ-Al2O3 and 14Fe/3Cu/1Ca/1Mn/γ-Al2O3. The catalysts were characterized by XRD, ICP, BET, FE-SEM, EDX, H2-TPR and TEM techniques. The performance of the catalysts was also evaluated in a fixed bed reactor under a pressure of 20 atm, a H2 to CO ratio of 1, a GHSV of 2 L h−1 g cat−1 and a temperature of 285 °C. Finally, the effect of Ca and Mn promoters individually and in combination with each other on catalysts' performance was investigated. CO conversion and product selectivity were calculated using the results of gas chromatography. The 14Fe/3Cu/2Mn/γ-Al2O3 catalyst exhibits a higher selectivity for C2–C4 short-chain hydrocarbons, while the 14Fe/3Cu/1Ca/1Mn/γ-Al2O3 catalyst displays a much better selectivity for C5+ long-chain hydrocarbons. The C5+ selectivity of the doubly-promoted catalyst was 61.99%, which was higher than those of Fe/Cu catalysts and singly-promoted catalysts, due to the synergistic effect of the two promoters. The doubly-promoted catalyst achieved higher CO conversion (77.6%) and yield (48.03%) than other prepared catalysts. This demonstrates that the amount of Ca and Mn promoters in the synthesized Fe-based catalysts has a great influence on the distribution of hydrocarbon products. The formation of methane and light hydrocarbons was restrained with the combination of calcium and manganese. [ABSTRACT FROM AUTHOR]

We explored solvent effect on the stability, dipole moment, polarizability and first hyperpolarizability of Fe(CO)4B12N12 complexes at MPW1PW91/6-311G(d,p) level of theory. These complexes were considered in the low spin states. The self-consistent reaction field theory (SCRF) based on conductor-like polarizable continuum model (PCM) was employed to illustration of the solvent influences. The relations between the parameters with solvent polarity functions (McRae and Suppan functions) were given. Also, relations of the wavenumbers values of the stretching of carbonyl ligands with the Kirkwood–Bauer–Magat equation (KBM) were provided. [ABSTRACT FROM AUTHOR]

For structures with a C2PO2 skeleton, a comparison of "single-and-half" phosphorus–oxygen bonds with single and double phosphorus–oxygen bonds is presented. The study is performed by considering the title structure, 63 analogous salt/zwitterionic structures with the [O–P=O]– moiety and 445 structures with a neutral O–P=O moiety retrieved from the Cambridge Structural Database. The average lengths of the single, "single-and-half " and double phosphorus-oxygen bonds were obtained as 1.58, 1.50, and 1.48 Å, which indicates the proximity of "single-and-half " bond lengths to double phosphorus–oxygen bond lengths. In the crystal structure of the title compound, the [NH2C5H4NH]+ cation, [(C6H5)2P(O)(O)]– anion and two independent water molecules are interconnected through relatively strong O–H⋅⋅⋅O and N–H⋅⋅⋅O hydrogen bonds, building a two-dimensional assembly along the ab plane. In this hydrogen-bond pattern, the oxygen atoms of the [O–P=O]– moiety act as double hydrogen-bond acceptors. [ABSTRACT FROM AUTHOR]

ABSTRACT As the world shifts towards renewable and sustainable energy sources, converting syngas into hydrocarbons using Fischer–Tropsch synthesis (FTS) catalysts is crucial. In this work, a series of copper‐modified iron‐based catalysts with cerium and strontium promoters supported on γ‐Alumina as follows were prepared using a wet‐impregnation method: FCA (18Fe/4Cu/γ‐Al2O3), FCCA (18Fe/4Cu/2Ce/γ‐Al2O3), FCSA (18Fe/4Cu/2Sr/γ‐Al2O3), and FCCSA (18Fe/4Cu/1Ce/1Sr/γ‐Al2O3). The phase, structure, and morphology of the catalysts were characterized using X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) specific surface area analysis, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), inductively coupled plasma–atomic emission spectrometry (ICP‐AES), hydrogen temperature‐programmed reduction (H2‐TPR), and hydrogen temperature‐programmed desorption (H2‐TPD). The impacts of Ce and Sr, individually and in combination, on the structure, adsorption, reduction, and catalytic performance of the catalysts were evaluated in a fixed bed reactor at 300°C, 2.0‐MPa pressure, a time of stream of 168 h, and an H2/CO ratio of 1. The CO conversion and product selectivity were calculated using gas chromatography results, highlighting the synergistic effect of Ce and Sr promoters on hydrocarbon product distribution. The doubly promoted FCCSA catalyst exhibited a high CO conversion rate of 77.65%, CO2 selectivity of 43.5%, C2‐C4 selectivity of 55.89%, C5+ selectivity of 85.62.0%, and a yield of 43.19%, surpassing FCA, FCCA, and FCSA catalysts. Similar characteristics, CO conversion, and product selectivity were achieved for FCCSA during long‐term 336‐h FTS runs, indicating stability. [ABSTRACT FROM AUTHOR]

Magnetic oxide nanocomposite (Fe3O4@SiO2@AgO), as the photocatalytic agent, was successfully synthesized through the simple chemical method. Besides, waste rice husk was used as the green source for silicon dioxide nanoparticles. The effect of AgO on the photocatalytic performance, degradation of phenol red under visible light, of Fe3O4@SiO2 nanocomposite was examined through the absorption spectroscopy technique. The maximum degradation by Fe3O4@SiO2 nanocomposite was 55% under visible light. On other hand, after combining Fe3O4@SiO2 nanocomposite with AgO, degradation percentage was increased to 89% thanks to the effect of AgO on the charge recombination process which leads to enhancement of the electron–hole separation. In order to test the catalytic application of Fe3O4@SiO2 nanocomposite, the impact of various parameters such as contact time, SiO2 concentration, and absorbent concentration on the desulfurization process of model oil was investigated. The efficiencies of removing dibenzothiophene from the fuel by Fe3O4 nanoparticles, SiO2 nanoparticles, and Fe3O4-SiO2 nanocomposite were 34.9%, 65.6%, and 78.2%, respectively, under optimum conditions. [ABSTRACT FROM AUTHOR]

The crystal structures of two single-enantiomer compounds, i.e. diphenyl [(R)-(+)-α-ethylbenzylamido]phosphate, C21H22NO3P or (C6H5O)2P(O)[NH-(R)-(+)CH(C2H5)(C6H5)] (I), and N-[(R)-(+)-α-ethylbenzyl]-P,P-diphenylphosphinic amide, C21H22NOP or (C6H5)2P(O)[NH-R-(+)CH(C2H5)(C6H5)] (II), were studied. The different environments at the phosphorus atoms, (O)2P(O)(N) and (C)2P(O)(N), allow the P O/P--N bond strengths to be compared, as well as the N--H...O P hydrogen-bond strengths, and P O/N--H vibrations. The following characteristics related to diastereotopic C6H5O/C6H5 groups in I/II were considered: geometry parameters, contributions to the crystal packing, solution 13C/¹H NMR chemical shifts, conformations, and NMR coupling constants. The phosphorus-carbon coupling constants nJPC (n = 2 and 3) in I and mJPC (m = 1, 2, 3 and 4) in II were evaluated. For a comparative study, chiral analogous structures were retrieved from the Cambridge Structural Database (CSD) and their geometries and conformations are discussed. [ABSTRACT FROM AUTHOR]