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Asparagine-modified magnetic graphene oxide as efficient green nanocatalyst for synthesis of chromenes and pyrano pyrazoles derivatives

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Scientific Reports 2025年第1期15卷 1-18页

作者： Khaleghiabbasabadi, Masoud Azarifar, Davood Taghavian, Hadi Hematian, Hadi Silvestri, Daniele Rezek, Bohuslav Bahrami, Behrokh Khodabakhshi, Saeed Institute for Nanomaterials Advanced Technology and Innovation Technical University of Liberec Liberec 46001 Czech Republic Faculty of Mechatronics Informatics and Interdisciplinary Studies Technical University of Liberec Liberec 46001 Czech Republic Department of Chemistry Bu-Ali Sina University Hamedan 65178 Iran Faculty of Electrical Engineering Czech Technical University in Prague Technická 2 Prague 16227 Czech Republic Department of Civil and Environmental Engineering Lamar University Beaumont TX United States Energy Safety Research Institute Swansea University Bay Campus Swansea SA1 8EN United Kingdom

The primary focus of this study involved the fabrication of a novel nanocatalyst Fe3O4-supported asparagine functionalized graphene oxide Fe3O4@GO-N-(Asparagine). The catalyst was synthesized through a four-step proce... 详细信息

The primary focus of this study involved the fabrication of a novel nanocatalyst Fe₃O₄-supported asparagine functionalized graphene oxide Fe₃O₄@GO-N-(Asparagine). The catalyst was synthesized through a four-step procedure. The chemical composition of Fe₃O₄@GO-N-(Asparagine) was examined using various analytical methods, including scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and a Raman. The Fe₃O₄@GO-N-(Asparagine) catalyst demonstrated remarkable catalytic action in the synthesis of 5-oxo-dihydropyrano[3,2-c]chromenes as well as dihydropyrano[2,3-c]pyrazole derivatives. The protocol offered several benefits, including short reaction times, the utilization of green solvents, outstanding product yields, and a straightforward work-up procedure. Eventually, density functional theory (DFT) computations were utilized to calculate several parameters, including energy levels, electrostatic potential, and chemical reactivity descriptors based on highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies. Based on the calculations obtained from DFT, it was determined that the type and position of functional groups on the synthesized compounds had the most significant impact on the calculations. © The Author(s) 2025.

关键词： density functional theory computations Dihydropyrano[2,3-c]pyrazole Fe3O4-Magnetized N-(asparagine)-functionalized graphene oxide Graphene oxide Magnetic nano catalyst Pyrano[3,2-c]chromenes

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DFT computation of the electron spectra of thiophene

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CANADIAN JOURNAL OF CHEMISTRY 2024年第7期102卷 425-430页

作者： Chong, Delano P. Univ British Columbia Dept Chem 2016 Main Mall Vancouver BC V6T 1Z1 Canada

Recent experiments on thiophene using synchrotron radiation stimulated the present density functional theory (DFT) study of the various types of electron spectroscopy using the DFT methods we developed in our laboratory. Besides the confirmation of the experimental interpretations, the results of the present study strongly validate the methods used for the various types of electron spectroscopy. The average absolute deviations of the DFT results for thiophene from experiment are 0.22 eV for vertical ionization energies of outer valence electrons, 0.10 eV for carbon 1s binding energies, 0.19 eV for vertical valence excitation energies, and 0.18 eV for X-ray absorption energies. The calculated carbon 1s binding energies for bithiophene and terthiophene are also within 0.1 eV of synchrotron experiment. We conclude that workers using synchrotron radiation to study electronic processes of gas-phase molecules can apply our DFT methods for the interpretation of their experimental results. Key words: thiophene, density functional theory computations, electron spectra, dimeric and trimeric oligothiophenes

关键词： thiophene density functional theory computations electron spectra dimeric and trimeric oligothiophenes

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Dinitrogen extrusion from diazidophenylborane:: Computational analysis of PhBN_x (x=6,4,2) isomers

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JOURNAL OF ORGANOMETALLIC CHEMISTRY 2006年第21期691卷 4480-4485页

作者： Bettinger, Holger F. Ruhr Univ Bochum Lehrstuhl Organ Chem 2 D-44780 Bochum Germany

The energies and structures of possible intermediates in the dinitrogen extrusion from diazidophenylborane 4a to give phenylborylene 11a were determined using density functional (B3LYP), multiconfigurational (CASSCF and MRMP2), and coupled cluster (CCSD(T)) computations in conjunction with basis sets of up to cc-pVTZ quality. Formation of 11a and nitrogen from 4a is an exothermic process (-21 kcal mol(-1)). The triplet electronic ground state of azidophenylborylnitrene 5a (PhBN4) is only 26 kcal mol(-1) higher in energy than 4a and the phenyl shift in 5a to yield N-azidophenyliminoborane 7a is highly exothermic. (c) 2006 Elsevier B.V. All rights reserved.

关键词： density functional theory computations azido boranes reactive intermediates borylene

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Mechanical Vibrations of Atomically Defined Metal Clusters: From Nano- to Molecular-Size Oscillators

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NANO LETTERS 2018年第11期18卷 6842-6849页

作者： Maioli, Paolo Stoll, Tatjana Sauceda, Huziel E. Valencia, Israel Demessence, Aude Bertorelle, Franck Crut, Aurelien Vallee, Fabrice Garzon, Ignacio L. Cerullo, Giulio Del Fatti, Natalia Univ Claude Bernard Lyon 1 Univ Lyon CNRS Inst Lumiere Matiere F-69622 Villeurbanne France Politecn Milan CNR IFN Dipartimento Fis Piazza L daVinci 32 I-20133 Milan Italy Max Planck Gesell Fritz Haber Inst D-14195 Berlin Germany Univ Nacl Autonoma Mexico Fac Estudios Super Iztacala Tlalnepantla 54090 Estado De Mexic Mexico Univ Claude Bernard Lyon 1 Univ Lyon CNRS Inst Rech Catalyse & Environm Lyon IRCELYON F-69622 Villeurbanne France Univ Nacl Autonoma Mexico Inst Fis Apartado Postal 20-364 Mexico City 01000 DF Mexico

Acoustic vibrations of small nanoparticles are still ruled by continuum mechanics laws down to diameters of a few nanometers. The elastic behavior at lower sizes (<1-2 nm), where nanoparticles become molecular clusters made by few tens to few atoms, is still little explored. The question remains to which extent the transition from small continuous mass solids to discrete-atom molecular clusters affects their specific low-frequency vibrational modes, whose period is classically expected to linearly scale with diameter. Here, we investigate experimentally by ultrafast time-resolved optical spectroscopy the acoustic response of atomically defined ligand-protected metal clusters Au-n(SR)(m) with a number n of atoms ranging from 10 to 102 (0.5-1.5 nm diameter range). Two periods, corresponding to fundamental breathing- and quadrupolar-like acoustic modes, are detected, with the latter scaling linearly with cluster diameters and the former taking a constant value. Theoretical calculations based on density functional theory (DFT) predict in the case of bare clusters vibrational periods scaling with size down to diatomic molecules. For ligand-protected clusters, they show a pronounced effect of the ligand molecules on the breathing-like mode vibrational period at the origin of its constant value. This deviation from classical elasticity predictions results from mechanical mass-loading effects due to the protecting layer. This study shows that clusters characteristic vibrational frequencies are compatible with extrapolation of continuum mechanics model down to few atoms, which is in agreement with DFT computations.

关键词： Ultrafast spectroscopy metal nanoparticles thiolate clusters acoustic vibrations elasticity density functional theory computations

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Fe, Ru, and Os-embedded graphitic carbon nitride as a promising candidate for NO gas sensor: A first-principles investigation

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MATERIALS CHEMISTRY AND PHYSICS 2019年 231卷 264-271页

作者： Basharnavaz, Hadi Habibi-Yangjeh, Aziz Kamali, Seyed Hossein Univ Mohaghegh Ardabili Fac Sci Dept Chem POB 179 Ardebil Iran

The adsorption behavior of NO gas on the pristine graphitic carbon nitride (gCN) and transition metal atoms (TM).embedded gCN systems (TM = Fe, Ru, and Os atoms) was investigated with density functional theory in solid state. The adsorption energy results revealed that the embedding of TM atoms can significantly improve the adsorption properties of NO gas on the gCN systems with high adsorption energy of -3.14 eV for Os-embedded gCN, compared with that on the pristine gCN (-0.54 eV). Our results indicated that the adsorption energy of NO gas on the Os-embedded system is much larger than those reported for the other adsorbents. Although NO gas was physisorbed on the pristine gCN, this gas was strongly chemisorbed over the TM-embedded systems. Furthermore, it was observed that the electronic and magnetic characteristics of gCN considerably modulated by embedding of transition metal atoms. The results of magnetic calculations displayed that Os-embedded gCN exhibited magnetic properties with magnetic moment of 0.77 mu(B), whereas Fe and Ru-embedded gCN systems are non-magnetic. Furthermore, it was found that the conductivity of TM-embedded gCN systems was more than that of the pristine system, due to the induced TM atoms impurity states in the band gap energy. In addition, the results displayed electron donation from d-orbitals of TM atoms to pi* orbital of NO gas for all of the TM-embedded gCN systems. Therefore, the results displayed that among all of the TM-embedded gCN systems, the Os-embedded gCN has the best adsorption characteristics for sensing and removing of NO gas from the environment.

关键词： Graphitic carbon nitride NO adsorption density functional theory computations

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13C NMR relaxation and computational study of anisole and derivatives in the solution state

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JOURNAL OF PHYSICAL ORGANIC CHEMISTRY 2012年第12期25卷 1374-1379页

作者： Ng, Soon Salleh, Faizah Md Xie, Yaoming Schaefer, Henry F., III Univ Malaya Dept Chem Kuala Lumpur 50603 Malaysia Univ Georgia Ctr Computat Quantum Chem Athens GA 30602 USA

13C NMR spinlattice relaxation times and nuclear Overhauser effects were measured at several temperatures for the methoxyl methyl carbon and the phenyl ring carbons in neat samples and in dilute cyclohexane solution for anisole, 4-methylanisole, and 4-chloroanisole. Similar measurements were made for 2-methylanisole, 2-methyl-4-bromoanisole, and 2,4,6-trimethylanisole in dilute cyclohexane solution. density functional theory (DFT) computations were performed on anisole, 4-chloroanisole and 2,4,6-trimethylanisole to obtain the minimum energy structures and the potential energy barriers to the internal rotations of the methoxyl group. The shortest distance between a methoxyl methyl hydrogen and the ortho hydrogen in anisole is 1.920?angstrom. The DFT results point to steric interactions that arise thereof as the principal source of the energy barriers to the internal rotation of the methyl or of the methoxyl group. The carbon relaxation data are consistent with the existence of noncovalent intermolecular interaction, especially pi?-?pi stacking interaction. The nuclear magnetic resonance and DFT results are discussed with reference to the rotational characteristics of the methoxyl methyl and the anisotropy in the reorientational motion of anisole and its derivatives in dilute cyclohexane solution. Copyright (c) 2012 John Wiley & Sons, Ltd.

关键词： 13C NMR T1 anisole anisotropic reorientational motion derivatives density functional theory computations internal rotations nuclear Overhauser effect noncovalent interactions steric hindrance

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RuN2 Monolayer: A Highly Efficient Electrocatalyst for Oxygen Reduction Reaction

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ACS APPLIED MATERIALS & INTERFACES 2020年第49期12卷 54517-54523页

作者： Jia, Jingjing Chen, Zhe Liu, Yuejie Li, Yafei Zhao, Jingxiang Harbin Normal Univ Coll Chem & Chem Engn Harbin 150025 Peoples R China Harbin Normal Univ Key Lab Photon & Elect Bandgap Mat Minist Educ Harbin 150025 Peoples R China Harbin Normal Univ Modern Expt Ctr Harbin 150025 Peoples R China Nanjing Normal Univ Jiangsu Collaborat Innovat Ctr Biomed Funct Mat Sch Chem & Mat Sci Jiangsu Key Lab New Power Batteries Nanjing 210023 Peoples R China

The transition metal-based nitride (TMN) holds great promise as catalysts with high efficiency for energy-related technologies. Herein, on the basis of global structure search and density functional theory calculations, a novel two-dimensional (2D) TMN was identified: RuN2 monolayer with tetracoordinated Ru atoms and isolated N=N dimers, which is revealed to possess high thermal, dynamic, and chemical stabilities as well as metallic nature, thus providing great feasibility for its practical application in electrochemical reactions. Remarkably, we found that the predicted RuN2 monolayer exhibits superior catalytic performance for the oxygen reduction reaction (ORR) with a rather high limiting potential (0.99 V) and an overwhelming four-electron reduction pathway selectivity. Thus, our results suggested the robust applicability of RuN2 monolayer as a novel non-Pt catalyst due to its excellent catalytic efficiency and outstanding selectivity for ORR, which not only proposes a new member to the hypercoordinate 2D TMN with novel properties, but also provides a feasible strategy to further develop novel TMN-based nanomaterials for electrocatalytic energy conversion.

关键词： metal nitride oxygen reduction reaction global structure search density functional theory computations electrocatalysis

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δ-SnS: An Emerging Bidirectional Auxetic Direct Semiconductor with Desirable Carrier Mobility and High-Performance Catalytic Behavior toward the Water-Splitting Reaction

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ACS APPLIED MATERIALS & INTERFACES 2021年第27期13卷 31934-31946页

作者： Zhang, Qiang Wang, Xian Yang, Shali Univ Shanghai Sci & Technol Coll Sci Shanghai 200093 Peoples R China

We propose a novel two-dimensional SnS allotrope (monolayer delta-SnS) based on an auxetic delta-phosphorene configuration using first-principles calculations. This monolayer appears to have outstanding stability as revealed by its energetic, kinetic, thermodynamic, and mechanic calculations, and it can withstand temperatures as high as 900 K. Monolayer delta-SnS is a wide direct-bandgap (2.354 eV) semiconductor, and its electron mobility is as high as similar to 1.25 x 10(3) cm(2) V-1 s(-1), higher than that of monolayer KTlO (similar to 450 cm(2) V-1 s(-1)) and MoS2 (similar to 200 cm(2) V-1 s(-1)). Optical absorption spectra, reaching up to the order of similar to 10(5) cm(-1), are obviously excellent in the visible-light region, suggesting efficient harvesting of solar radiation. Because of its unique atomic motif, monolayer delta-SnS presents an unusual bidirectional auxetic effect: a high negative in-plane Poisson's ratio (-0.048 and -0.068), which is larger than those for many recently reported two-dimensional auxetic materials, e.g., black phosphorene (-0.027), borophene (-0.04), and monolayer penta-B2N4 (-0.02). The bandgap and band edge can be substantially manipulated under strain to meet the requirement of the water-splitting reaction. Particularly, when pH = 7, suitable band-edge alignments and small overpotentials of the photocatalytic OER (oxygen evolution reaction) and HER (hydrogen evolution reaction) appear, endowing monolayer delta-SnS with great potential as an efficient visible-light-driven bifunctional photocatalyst for water splitting.

关键词： density functional theory computations negative in-plane Poisson's ratio photocatalytic water splitting hydrogen evolution reaction oxygen evolution reaction bifunctional photocatalyst

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Proton solvation in protic and aprotic solvents

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JOURNAL OF COMPUTATIONAL CHEMISTRY 2016年第12期37卷 1082-1091页

作者： Rossini, Emanuele Knapp, Ernst-Walter Free Univ Berlin Inst Chem & Biochem Fabeckstr 36a D-14195 Berlin Germany

Protonation pattern strongly affects the properties of molecular systems. To determine protonation equilibria, proton solvation free energy, which is a central quantity in solution chemistry, needs to be known. In this study, proton affinities (PAs), electrostatic energies of solvation, and pK(A) values were computed in protic and aprotic solvents. The proton solvation energy in acetonitrile (MeCN), methanol (MeOH), water, and dimethyl sulfoxide (DMSO) was determined from computed and measured pK(A) values for a specially selected set of organic compounds. pK(A) values were computed with high accuracy using a combination of quantum chemical and electrostatic approaches. Quantum chemical density functional theory computations were performed evaluating PA in the gas-phase. The electrostatic contributions of solvation were computed solving the Poisson equation. The computations yield proton solvation free energies with high accuracy, which are in MeCN, MeOH, water, and DMSO -255.1, -265.9, -266.3, and -266.4 kcal/mol, respectively, where the value for water is close to the consensus value of -265.9 kcal/mol. The pK(A) values of MeCN, MeOH, and DMSO in water correlates well with the corresponding proton solvation energies in these liquids, indicating that the solvated proton was attached to a single solvent molecule. (c) 2016 Wiley Periodicals, Inc.

关键词： protic and aprotic solvents pK(A) computation proton solvation proton affinity density functional theory computations electrostatic energy computation

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Gas-phase complexes of Ni²⁺ and Ca²⁺ with deprotonated histidylhistidine (HisHis): A model case for polyhistidyl-metal binding motifs

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JOURNAL OF MOLECULAR SPECTROSCOPY 2017年 332卷 38-44页

作者： Peckelsen, Katrin Martens, Jonathan Berden, Giel Oomens, Jos Dunbar, Robert C. Meijer, Anthony J. H. M. Schaefer, Mathias Univ Cologne Inst Organ Chem Dept Chem Greinstr 4 D-50939 Cologne Germany Radboud Univ Nijmegen Inst Mol & Mat FELIX Lab Toernooiveld 7c NL-6525 ED Nijmegen Netherlands Univ Amsterdam Sci Pk 904 NL-1098 XH Amsterdam Netherlands Case Western Reserve Univ Dept Chem Cleveland OH 44106 USA Univ Sheffield Dept Chem Sheffield S3 7HF S Yorkshire England

In the complex formed between the calcium cation (Ca2+) and a deprotonated HisHis dipeptide, the complex adopts a charge solvation (CS) structure. Ca2+% a weak binding main group metal cation, interacts with the oxygens of the peptide carbonyl moiety and the deprotonated C-terminus. In contrast, the much stronger binding Ni2+ cation deprotonates the peptide nitrogen and induces an iminolate (Im) ligand structure in the [Ni(HisHis-H)](+) complex ion. The combination of infrared multiple-photon dissociation (IRMPD) spectroscopy and quantum chemistry evidence these two representative binding motifs. The iminolate coordination pattern identified and characterized in the [Ni(HisHis-H)](+) complex serves as a model case for nickel complexes of poly-histidyl-domains and is thereby also of interest to better understand the fundamentals of immobilized metal ion affinity chromatography as well as of Ni co-factor chemistry in enzymology. (C) 2016 Elsevier Inc. All rights reserved.

关键词： Infrared multiple photon dissociation IRMPD spectroscopy Nickel and calcium-histidylhistidine complexes density functional theory computations Iminolate and charge solvation binding patterns

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