POLYHEDRON
·
2016
·
IF 2.108
Tongguang Sun,Fei Liang,Xinyuan Zhang,Heng Tu,Zheshuai Lin,Guochun Zhang,Yicheng Wu
Single crystals of three new organic–inorganic hybrid compounds, tri[1-(diaminomethylene)uronium] hexachlorobismuthate ((C 2 H 7 N 4 S) 3 BiCl 6 ·H 2 O, HATU-BCH), bis[1-(diaminomethylene)uronium] pentabromobismuthate, ((C 2 H 7 N 4 S) 2 BiBr 5 , HATU-BB), and bis [3,5-diamino-1,2,4-thiadiazol-2-ium] pentaiodobismuthate ((C 2 H 5 N 4 S) 2 BiI 5 , OHATU-BI), have been successfully grown by slow evaporation method. Their structures were determined by single - crystal X-ray diffraction, in which all anion sublattice structures consist of hexahalobismuthates octahedra with different connection modes involving isolated, shared-corner, and shared-edge. The spectra characters were studied by Infrared and Raman spectra, which interpreted by calculation of the density functional theory (DFT) method and diffuse reflectance spectra. Thermal properties were characterized by thermal gravimetric analysis and differential scanning calorimetry.
研究领域:
材料化学
·
晶体工程
·
配位化学
·
光谱学
·
热分析
·
计算化学
✓ 已验证
DOI
高影响因子
POLYMER
·
2018
·
IF 3.483
Jianting Zhang,Yanhong Cui,Xiaoqing Li,Hanqiang Yao,Deming Zhao,Ningren Jin,Jianrong Gao
A novel poly(hydroxy-p-phenylenebenzobisoxazole) (HPBO) with superior comprehensive properties was synthesized via self-polymerization of composite salt monomer (HD). The molecular simulation results of relative total energies and the activation energies indicated that the meta-carboxyl group was the active site of condensation reaction which was carried out by amidation . Further molecular simulation results showed that the most probable configuration of HPBO was ordered P1 conformation, and the conjugation and stability of HPBO were enhanced by increasing the number of repeat units. The introduction of mono-hydroxyl group contributes to the formation of intramolecular hydrogen bonds of HPBO molecules, which made HPBO exhibit the molecular structure of the two-dimensional conjugate & coplanar and improved the thermal stability relative to PBO and DHPBO. The simulation results were verified by corresponding experimental investigation.
研究领域:
高分子化学
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材料科学
·
计算化学
·
物理化学
·
功能材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2024
·
IF 3.7
Xiangyi Kong,Jie Cheng,Wei Meng,Shujing Han,Zhen Song,Zhiwen Qi
As a volatile organic compound (VOC), styrene can pose significant risks to human health and environment if released into the air without proper treatment. Absorption based on ionic liquids (ILs) has been widely regarded as a promising VOC treatment approach, whereas there is limited research on capturing styrene by ILs. In this work, a multilevel framework was proposed to screen IL absorbents from the largest number of cation-anion combinations in the latest COSMObase. The COSMO-RS model is applied to estimate the absorption and desorption potentials of all IL candidates for styrene capture based on solubility prediction, while important physical properties of them namely melting point, viscosity, and toxicity are estimated by a recently-reported deep learning model. A parallel screening specific to the commercially available ILs in the initial candidate database was also performed. The top-ranked three ILs, identified in both scenarios with and without limiting the commercially availability, were further evaluated in a simulated absorption-desorption process in Aspen Plus. The most promising ILs in each scenario were figured out, which vividly demonstrates the value of discovering novel ILs.
研究领域:
环境化学
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化学工程
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绿色溶剂
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计算化学
·
大气污染控制
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·Vol. 13
·期 2
·1985-2000
·
IF 1.5
Zhe Zhang,Le Ruan,Weipeng Zhang,Yuzeng Lyu,Wei Shang,Yuqing Wen,Xiuying Li,Ling Wu,Yanni Jiao
The triazol-3-ylamine and three different kinds of Schiff base compounds are self-assembled on bronze surface. Electrochemical impedance spectroscopy and potentiodynamic polarization measurements show that the triazol-3-ylamine and Schiff base self-assembled films can protect bronze from corrosion in 0.5 M HCl solution. The corrosion efficiency increases with the self-assembly time increasing and reaches a stable value after 8 h. The highest corrosion efficiency of the bronze electrode modified with self-assembled films reaches 95.81% after immersing in 0.005 M 2,4-Dibromo-6-[(4H-[1,2,4]Triazol-3-ylimino)-methyl]-phenol Schiff base solution for 10 h. X-ray photoelectron spectroscopy and scanning electrochemical microscope are used to characterize the inhibitive ability of the self-assembled films. Quantum chemical calculations and dynamic simulations indicate that the triazol-3-ylamine and Schiff bases molecules can absorb on the copper surface via chemisorption. The adsorption energy increases with the number of aromatic rings.
研究领域:
材料腐蚀与防护
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物理化学
·
表面科学
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电化学
·
计算化学
✓ 已验证
DOI
高影响因子
FLAVOUR AND FRAGRANCE JOURNAL
·
2012
·Vol. 27
·期 5
·378-385
·
IF 1.424
Zhangfu Zeng,Yanxiong Fang,Hongbing Ji
The reason for low encapsulation efficiency of vanillin compared to p -hydroxybenzaldehyde within β -cyclodextrin was investigated. Fourier transform infrared spectra proved intermolecular interaction between guest and β -cyclodextrin. UV–visible studies indicated that vanillin and p -hydroxybenzaldehyde form 1:1 inclusion complexes with β -cyclodextrin. Nuclear magnetic resonance and quantum computational methods gave the most favourable orientation in which the guest molecule (vanillin or p -hydroxybenzaldehyde) is totally sequestered in the hydrophobic cavity of the cyclodextrin with the phenolic end located near the primary hydroxyls of the β -cyclodextrin and the aldehyde group near the secondary hydroxyls with hydrogen bonding formation. Encapsulation efficiency of the β -cyclodextrin inclusion with vanillin is about 29% lower than that with p -hydroxybenzaldehyde. This result could be attributable to the effect that the side chain methoxy group weakened the guest/host non-covalent intermolecular interaction, specifically, hydrogen bond interaction. Copyright © 2012 John Wiley & Sons, Ltd.
研究领域:
药物化学
·
超分子化学
·
分析化学
·
药剂学
·
分子识别
·
计算化学
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2016
·
IF 9.307
Qiaofei Zhang,Xin-Ping Wu,Yakun Li,Ruijuan Chai,Guofeng Zhao,Chunzheng Wang,Xue-Qing Gong,Ye Liu,Yong Lu
A Ni-foam-structured PdNi nanoalloy catalyst engineered from nano- to macro-scales has been successfully fabricated for the catalytic deoxygenation of coalbed methane (CBM). The catalyst was obtainable by embedment of Pd nanoparticles onto Ni-foam substrate via a galvanic exchange reaction method and subsequent in situ activation in the reaction, which was active at low temperature, selective (no CO formation), and oscillation free in this CH4-rich catalytic combustion process. Special Pd@NiO (Pd nanoparticles partially wrapped by tiny NiO fragments) ensembles were formed in the galvanic deposition stage and could merely be transformed into PdNi nanoalloys in the real reaction stream at elevated temperatures (e.g., 450 °C or higher). Density functional theory (DFT) calculations were carried out to reveal the role of Ni decoration at Pd in PdNi nanoalloy catalyst for the CBM deoxygenation. By nature, the Pd–Ni alloying modified the electronic structure of surface Pd and led to a decrease in the O adsorption energy, which can be taken as the activity descriptor for the CBM deoxygenation. A reaction kinetic study indicated that the Ni decoration at Pd by Pd–Ni alloying lowered the apparent activation energy in comparison to the pristine Pd catalyst, while leading to an increase of the reaction order of O2 from −0.6 at Pd catalyst to −0.3. The foam-structured PdNi nanoalloy catalyst thus offered enhanced low-temperature activity and the elimination of oscillating phenomena as the result of a transient balance obtained between the cycles of O2 adsorption/activation and CH4 oxidation.
研究领域:
催化化学
·
材料科学
·
能源工程
·
计算化学
·
环境化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 11
·6242-6250
·
IF 3.108
Pengchao Wang,Yongjun Hu,Huaqi Zhan,Jiaxin Chen
Glycoaldehyde (GA, HOCH2CHO) is the simplest sugar unit of the carbohydrates and the only sugar to have been detected in interstellar space to date. In the present report, the conformation of GA and its flexible hydrated complexes have been investigated in the gas phase by using mass-selected infrared (IR) spectroscopy based on vacuum-ultraviolet single photon ionization (118 nm). With the aid of theoretical calculations, the neutral GA bearing a ring-type intramolecular hydrogen bonding interaction was confirmed to be the dominant isomer in the gas phase. Moreover, the water molecules in the monohydrated complexes preferentially broke the intramolecular hydrogen bond and bridged the carbonyl oxygen and hydroxyl hydrogen of GA with two additional intermolecular H-bonds, revealing the “working rules” governing preferred binding. The theoretical results confirmed that the existence probability of the two lowest energy conformations stabilized by two intermolecular hydrogen bonds would be larger than that of the next two isomers with one intramolecular plus one intermolecular hydrogen bond. Structural investigation of hydrated GA conformers has revealed that the water molecules play the role of a bridge through intermolecular H-bonds, achieving selective population of specific GA molecular conformations. These results suggest that these hydrogen-bonded bridge structures in the hydrated complexes may provide good models for recognition in larger systems.
研究领域:
物理化学
·
天体化学
·
分子光谱学
·
计算化学
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2022
·
IF 10.508
Ruixiang Mi,Sanlue Hu,Zewen Xiao
Motivated by the success of metal halide perovskites in the field of optoelectronics, antiperovskites, which have the same crystal lattice as that of perovskites but with switched anion and cation positions, have recently been considered as potential candidates for optoelectronic applications. However, the best-known oxyhalide antiperovskites A3OX (A = alkali metal; X = halogen) generally exhibit very large bandgaps due to their immensely strong ionicity. In this work, we report the theoretical design and experimental verification of rock-salt-ordered double antiperovskites with reduced bandgaps. Each of two O anions in the A3OX oxyhalide antiperovskites is replaced with the combination of a trivalent N anion and a monovalent Y″ anion, yielding A6NY″X2 double antiperovskites. Density functional theory (DFT) calculations reveal that compared with the A3OX antiperovskites, the A6NY″X2 double antiperovskites have significantly reduced bandgaps, mainly due to high-lying N 2p orbitals. On the other hand, the p orbitals of the Y″ anion lie far below the N 2p orbitals and almost do not affect the bandgaps. Guided by the DFT calculations, we successfully synthesized four nitrohalide double antiperovskites, that is, Li6NBrBr2, Li6NII2, Li6NClBr2, and Li6NBrI2, and verified the predicted bandgap reductions. Our work provides strategies for designing double antiperovskites and expands the large family of antiperovskites.
研究领域:
材料科学
·
凝聚态物理
·
计算化学
·
光电子学
·
无机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY A
·
2011
·
IF 2.732
Min Xie,Yajing Qi,Yongjun Hu
2-Phenylethylamine (PEA) is the simplest aromatic amine neurotransmitter, as well as one of the most important. In this work, the conformational equilibrium and hydrogen bonding in liquid PEA were studied by means of Raman spectroscopy and theoretical calculations (DFT/MP2). By changing the orientation of the ethyl and the NH2 group, nine possible conformers of PEA were found, including four degenerate conformers. Comparison of the experimental Raman spectra of liquid PEA and the calculated Raman spectra of the five typical conformers in selected regions (550−800 and 1250−1500 cm−1) revealed that the five conformers can coexist in conformational equilibrium in the liquid. The NH2 stretching mode of the liquid is red-shifted by ca. 30 cm−1 relative to that of an isolated PEA molecule (measured previously), implying that intermolecular N−H···N hydrogen bonds play an important role in liquid PEA. The relative intensity of the Raman band at 762 cm−1 was found to increase with increasing temperature, indicating that the anti conformer might be favorable in liquid PEA at room temperature. The blue shift of the band for the bonded N−H stretch with increasing temperature also provides evidence of the existence of intermolecular N−H···N hydrogen bonds.
研究领域:
物理化学
·
光谱学
·
计算化学
·
分子结构
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2022
·
IF 4.177
Lei Zhang,Wenguang Hu,Mu He,Kun Xu,Zheng Pan
Halide perovskite materials exhibit poor optoelectronic properties under hostile conditions, such as water, therefore interpretable machine learning models of halide perovskite systems under hostile conditions are necessary. In this article, we employ machine learning methods to explore cosensitizer-based halide perovskite films in aqueous solution, with the introduction of multiple types of light-absorbing molecules to modify the perovskite/TiO2 interface. Chemical insights are provided based on the analysis of the molecular descriptors, suggesting the importance of the electrostatic and electrotopological features as well as the chemical compositions and functional groups of the interlayer molecules. Experiments are carried out to validate the machine learning model, and fair agreements between the machine learning model and the experimental results are achieved; this leads to the identification of alternative cosensitizers that offer promising optoelectronic properties in aqueous solution. This article highlights the model interpretability to predict and understand the halide perovskite-based films, and the approach outlined here can be generalized to design other surface systems.
研究领域:
材料科学
·
机器学习
·
光伏技术
·
表面化学
·
计算化学
✓ 已验证
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2018
·
IF 3.972
Yang Song,Zhihui Cai,Zhixian Li,Guoqiang Guan,Yanbin Jiang
Crystallization is one of the most important unit operations in the quality control of pharmaceutical products. For this study, a polymer-induced heteronucleation method was selected to investigate the effect of nylon 66 (PA66), polyester (PET), and polypropylene (PP) films on the crystal growth of paracetamol by coupling experiments with modeling. The result of induction time indicated that the order of induced effect was PA66 > PET > PP > no template. X-ray photoelectron spectroscopy results indicated the different functional groups on the surface of films. The crystal habits and powder X-ray diffraction results indicated that preferential orientation along certain facets occurred for PA66 and PET, and the results of in situ Raman microscopy verified the different concentration trends near different films, which is consistent with the preferential orientation effect of films. The results of molecular simulation indicated that the difference in van der Waals and electrostatic interaction, as well as H-bond donor/acceptor on the polymer films, is the origin of the preferential orientation effect for paracetamol crystallization. The PP film modified with similar functional groups of PA66 on surfaces caused the same preferential orientation effect as PA66, which verified the functional-induced mechanism of the preferential orientation. This study could contribute to the investigation of the mechanism of polymer-induced heteronucleation and screen out the efficient templates.
研究领域:
药物结晶
·
材料科学
·
聚合物科学
·
计算化学
·
成核与晶体生长
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2020
·
IF 3.687
Juan Liu,Wen-Ying Li,Jie Feng,Xiang Gao
The hydrodenitrogenation of nitrogen-containing heterocycles over noble metals has fundamental importance for energy and environmental science. To develop more efficient catalyst, mechanistic investigation has been conducted with a method combining in situ Fourier transformation infrared experiments and density functional theory calculations in this work. The in situ experiments indicate flatly adsorbed pyridine molecules convert to pyridinium and α -pyridyl species at higher temperature on metallic Pt of Pt/γ-Al 2 O 3 catalysts. Pyridine hydrogenation distinctly takes place at 150 °C with the appearance of methylene stretching vibrations, and a stepwise mechanism is identified as the temperature further increases. The adsorption, hydrogenation and hydrogenolysis of pyridine on Pt are studied in detail by theoretical calculations. In line with these findings, the geometry optimization confirms pyridine preferentially adsorbs on Pt(111) and Pt(211) both in a parallel configuration. Based on the Langmuir–Hinshelwood mechanism, the results show successive hydrogenation markedly lowers the energy barrier for subsequent hydrogenolysis. The C N bond cleavage occurs via nucleophilic attack of pentahydropyridine, rather than piperidine, which determines the reaction products, including piperidine, n -pentylamine and n -pentane. The comparative study reveals both hydrogenation and hydrogenolysis are kinetically and thermodynamically more competitive on Pt(211) than Pt(111). Especially for hydrogenolysis, the coordinatively unsaturated Pt step atoms play an essential role in C N bond cleavage. Thus, hydrogenolysis is more geometric‒dependent than hydrogenation. This provides instructive information for the design of catalysts with adjustable product selectivity.
研究领域:
催化化学
·
环境科学
·
计算化学
·
能源科学
·
表面化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）