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NiCo/Al_(2)O_(3)nanocatalysts for the synthesis of 5-amino-1-pentanol and 1,5-pentanediol from biomass-derived 2-hydroxytetrahydropyran

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Green chemical Engineering 2024年第1期5卷 119-131页

作者： Jian Yang Jia Zhang Enrico Benassi Xuemei Li Hailong Liu Weiguo Fang Junying Tian Chungu Xia Zhiwei Huang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China School of Petrochemical Engineering Lanzhou University of TechnologyLanzhou730050China Novosibirsk State University Novosibirsk630090Russia University of Chinese Academy of Sciences Beijing100049China

Al_(2)O_(3)-supported monometallic Ni,Co,and bimetallic Ni-Co nanocatalysts originated from layered double hydroxide precursors were synthesized by co-precipitation method,and used for the synthesis of useful 5-amino-1-pentanol(5-AP)and 1,5-pentanediol(1,5-PD)by reductive amination(RA)or direct hydrogenation of biofurfuralderived 2-hydroxytetrahydropyran(2-HTHP),*** both reactions,the yield of the target products decreased monotonously with the increasing amounts of Co in the NiCo/Al_(2)O_(3)catalysts,owing probably to the replacement of highly reactive Ni by Co component with inferior hydrogenation activity at the low reaction temperature of 60℃.However,the incorporation of Co could improve the reducibility of the NiCo/Al_(2)O_(3)bimetallic catalysts and promote the reaction stability of the catalysts,especially for Ni_(2)Co1/Al_(2)O_(3),in both reactions with over 180 h *** of the catalysts before and after the reaction showed that the incorporating Co could inhibit the sintering of metal particles and hinder the surface oxidation of the more reactive Ni0species,thanks to the formation of Ni-Co alloy in the bimetallic ***-based modeling of the reaction mechanisms is also performed,supporting the reaction pathway proposed previously and also the much higher activity of Ni in the RA of 2-HTHP as compared with Co.

关键词： NiCo bimetallic catalysts Layered double hydroxide Reductive amination Amino alcohol quantum chemical calculations

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Synthesis,Structure and chemical Bonding of Polyantimony Clusters Containing Coinage Metals[M_(2)Sb_(14)]^(4-)(M=Cu,Ag)

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Chinese Journal of Chemistry 2024年第6期42卷 617-622页

作者： Wei-Xing Chen Yu-He Xu Cui-Cui Wang Lei Qiao Zi-Yan Guo Wen-Juan Tian Zhong-Ming Sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin300350 China Institute of Molecular Science Shanxi UniversityTaiyuanShanxi030006 China

Binary polyantimony clusters,namely[Cu_(2)Sb_(14)]^(4–) and [Ag_(2)Sb_(14)]^(4–),containing coinage metals,were successfully synthesized and characterized,in which two homoatomic Sb73–subunits are bridged by two coinage metals in η^(4):η^(1) and η^(1):η^(1) coordination modes,***[M_(2)Sb_(14)]^(4-),two bridging Cu ions and two Sb atoms form a planar rhombic unit,which was revealed to have antiaromatic properties by theoretical *** electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M^(+) ions.

关键词： Polyantimony cluster Copper Silver Antiaromaticity Metallophilic interaction quantum chemical calculations

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Structural Evolution and Electronic Properties of Au2Gen-/0（n=1-8） Clusters: Anion Photoelectron Spectroscopy and Theoretical calculations

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Chinese Journal of chemical Physics 2019年第2期32卷 229-240,I0003页

作者： Sheng-Jie Lu Hong-Guang Xu Xi-Ling Xu Wei-Jun Zheng Department of Chemistry and chemical Engineering Heze University Heze 274015 China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Department of Chemistry COMSATS University Islamabad Abbottabad-Campus Pakistan University of Chinese Academy of Sciences Beijing 100049 China

Investigating the structures and properties of Au-Ge mixed clusters can give insight into the microscopic mechanisms in gold-catalyzed Ge films and can also provide valuable information for the production of germanium-based functional materials. In this work, size-selected anion photoelectron spectroscopy and theoretical calculations were used to explore the structural evolution and electronic properties of Au2Gen^-/0 (n=1-8) clusters. It is found that the two Au atoms in Au2Gen^-/0 (n=1-8) showed high coordination numbers and weak aurophilic interactions. The global minima of Au2Gen- anions and Au2Gen neutrals are in spin doublet and singlet states, respectively. Au2Gen- anions and Au2Gen neutrals showed similar structural features, except for Au2Ge4^-/0 and Au2Ge5^-/0. The C2v symmetric V-shaped structure is observed for Au2Ge1^-/0, while Au2Ge2^-/0 has a C2v symmetric dibridged structure. Au2Ge3^-/0 can be viewed as the two Au atoms attached to different Ge-Ge bonds of Ge3 triangle. Au2Ge4- has two Au atoms edge-capping Ge4 tetrahedron, while Au2Ge4 neutral adopts a C2v symmetric double Au atoms face-capping Ge4 rhombus. Au2Ge5-8^-/0 show triangular, tetragonal, and pentagonal prism-based geometries. Au2Ge6 adopts a C2v symmetric tetragonal prism structure and exhibits σ plus π double bonding characters.

关键词： Photoelectron spectroscopy Transition metal Germanium cluster Structural evolution quantum chemical calculations

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Ultrafast proton transfer dynamics of 2-(2'-hydroxyphenyl)benzoxazole dye in different solvents

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Chinese Physics B 2022年第2期31卷 606-612页

作者： Simei Sun Song Zhang Jiao Song Xiaoshan Guo Chao Jiang Jingyu Sun Saiyu Wang Huangshi Key Laboratory of Photoelectric Technology and Materials College of Physics and Electronic ScienceHubei Normal UniversityHuangshi 435002China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China Hubei Key Laboratory of Pollutant Analysis&Reuse Technology College of Chemistry and Chemical EngineeringHubei Normal UniversityHuangshi 435002China

The excited-state intramolecular proton transfer of 2-(2-hydroxyphenyl)benzoxazole dye in different solvents is investigated using ultrafast femtosecond transient absorption spectroscopy combined with quantum chemical *** conversion from the syn-enol configuration to the keto configuration is proposed as the mechanism of excited-state intramolecular proton *** duration of excited-state intramolecular proton transfer is measured to range from 50 fs to 200 fs in different *** time is strongly dependent on the calculated energy gap between the N-S;and T-S;structures in the S;*** the proton transfer reaction coordinate,the vibrational relaxation process on the S;state potential surface is *** duration of the vibrational relaxation process is determined to be from8.7 ps to 35 ps dependent on the excess vibrational energy.

关键词： proton transfer vibrational relaxation femtosecond transient absorption spectroscopy quantum chemical calculations

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Theoretical Investigation on Photoionization and Dissociative Photoionization of Toluene

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Chinese Journal of chemical Physics 2017年第3期30卷 303-311,I0001,I0002页

作者：赵玉杰詹友胜李李李欣连相宇黄培盛六四陈军东华理工大学教育部核技术应用工程研究中心南昌330013 东华理工大学核科学与工程学院南昌330013 中国科学技术大学核科学技术学院国家同步辐射实验室合肥230029

The photoionization and dissociation photoionization of toluene have been studied using quantum chemistry methods. The geometries and frequencies of the reactants, transition states and products have been performed at B3LYP/6-311＋＋G（d,p） level, and single-point energy calculations for all the stationary points were carried out at DFT calculations of the optimized structures with the G3B3 level. The ionization energies of toluene and the ap- pearance energies for major fragment ions, C7H7＋, C6H5＋, C5H6＋, C5H5＋, are determined to be 8.90, 11.15 or 11.03, 12.72, 13.69, 16.28 eV, respectively, which are all in good agree- ment with published experimental data. With the help of available published experimental data and theoretical results, four dissociative photoionization channels have been proposed： CTHT＋＋H, C6Hs＋＋CH3, C5H6＋WC2H2, CsHs＋＋C2H2＋H. Transition structures and intermediates for those isomerization processes are determined in this work. Especially, the structures of C5H6＋ and C5H5＋ produced by dissociative photoionization of toluene have been defined as chain structure in this work with theoretical calculations.

关键词： quantum chemical calculations Toluene Dissociative photoionization mech-anism Density functional theory Transition states

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Role of water on the H-abstraction from methanol by ClO

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Journal of Environmental Sciences 2018年第9期30卷 89-98页

作者： Shanshan Tang Narcisse T.Tsona Junyao Li Lin Du Environment Research Institute Shandong University Jinan 250100 China

The influence of a single water molecule on the reaction mechanism and kinetics of hydrogen abstraction from methanol （CH3OH） by the CIO radical has been investigated using ab initio calculations. The reaction proceeds through two channels： abstraction of the hydroxyl H-atom and methyl H-atom of CH30H by CIO, leading to the formation of CH30 ＋ HOC1 （＋H20） and CH20H ＋ HOC1 （＋ H20）, respectively. In both cases, pre- and post-reactive complexes were located at the entrance and exit channel on the potential energy surfaces. Results indicate that the formation of CH2OH ＋ HOC1 （＋H20） is predominant over the formation of CH30 ＋ HOC1 （＋H20）, with ambient rate constants of 3.07 x 10^-19 and 3.01 x 10^-23 cm^3/（***）, respectively, for the reaction without water. Over the temperature range 216.7-298.2 K, the presence of water is seen to effectively lower the rate constants for the most favorable pathways by 4-6 orders of magnitude in both cases. It is therefore concluded that water plays an inhibitive role on the CH30H ＋ ClO reaction under tropospheric conditions.

关键词： Radical-molecule complex H-abstraction reaction Reaction rate constants quantum chemical calculations

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Computational studies of the structure and cation-anion interactions in 1-ethyl-3-methylimidazolium lactate ionic liquid

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Science China Chemistry 2012年第8期55卷 1548-1556页

作者： HE HongYan ZHENG YanZhen CHEN Hui ZHANG XiaoChun YAO XiaoQian ZHANG SuoJiang Beijing Key Laboratory of Ionic Liquids Clean Process Chinese Academy of SciencesBeijing 100190China College of chemistry and chemical Engineering Graduate University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Bioorganic Phosphorous Chemistry and chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China

quantum chemical calculations of the structures and cation-anion interaction of 1-ethyl-3-methylimidazolium lactate ([Emim][LAC]) ion pair at the B3LYP/6-31++G** theoretical level were performed. The relevant geometrical characteristics, energy properties, intermolecular H-bonds (H-bonds), and calculated IR vibrations with respect to isolated ions were systematically discussed. The natural bond orbital (NBO) and atoms in molecule (AIM) analyses were also employed to understand the nature of the interactions between cation and anion. The five most stable geometries were verified by analyzing the relative energies and interaction energies. It was found that the most of the C-H···O intermolecular H-bonds interactions in five stable conformers have some covalent character in nature. The elongation and red shift in IR spectrum of C-H bonds which involve in H-bonds is proved by electron transfers from the lone pairs of the carbonyl O atom of [LAC] to the C-H antibonding orbital of the [Emim]+. The interaction modes are more favorable when the carbonyl O atoms of [LAC] interact with the C2-H of the imidazolium ring and the C-H of the ethyl group through the formation of triple H-bonds.

关键词： interionic interaction structure hydrogen bond lactate-based ionic liquid quantum chemical calculations

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Effect of conical intersection of benzene on non-adiabatic dynamics

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Chinese Physics B 2022年第8期31卷 367-371页

作者： Duo-Duo Li Song Zhang State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

The effect of conical intersection on the excited dynamics of benzene is studied by ab initio theory of electronic structure,which provides an important insight into photophysical and photochemical *** on the CASSCF(6,6)/6-31+G(d,p)method,the topological structures of conical intersections S_(1)/S and S_(2)/S_(1)of benzene,as well as the optimal structures of the ground state(S)and excited states(S_(1),S_(2)),are *** energy minima of the S_(1)state and S_(2)state are estimated at 4.608 e V and 6.889 e V,*** addition,the energy values of the conical intersections of S_(1)/S and S_(2)/S_(1)are predicted to be 5.600 e V and 6.774 e *** to the topological structures and energy values of the S_(2)/S_(1)and S_(1)/S conical intersections,the photophysical behavior of benzene excited to the S_(2)state and the effects of the S_(2)/S_(1)and S_(1)/S conical intersections are discussed in detail.

关键词： conical intersection nonadiabatic dynamics ultrafast relaxation quantum chemical calculations

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All-electron ab initio calculations of YBa_2Cu_3O_7 with self-consistence crystal field

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Science China Chemistry 1995年第8期38卷 927-933页

作者：刘洪霖陈念贻 Shanghai Institute of Metallurgy Chinese Academy of SciencesShanghai 200050China

The quantum chemical calculations of cluster YBa_2Cu_3O_7 considering all electrons have been per- formed by using the ab initio HF method with self-consistence crystal field.A Hartree-Fork surface potential is proposed to make an asymmetric duster model possess a relatively symmetric potential field and to obtain a relatively symmetric electronic structure,electronic distributions,frontier orbitals,and bond order,*** suggestions that there exists a covalent bonding complex,[CuO_2-O-CuO-O-Cu_2]^(6,8-),in the cell unit of the crystal,and the cell units are connected with each other by ionic bonds along the c direction of the crys- tal lattice are offered based on the chemical bonding characteristics from the calculated *** important contribution of the apical oxygen to superconductivities is emphasized as well.

关键词： YBa_2Cu_3O_7 superconductivity quantum chemical calculations

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Novel gaseous transient species:generation and characterization

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Science China Chemistry 2007年第2期50卷 145-169页

作者： ZENG XiaoQing1,2 & WANG DianXun11 State Key Laboratory for Structural Chemistry of Unstable and Stable Species,Institute of Chemistry,Chinese Academy of Sci-ences,Beijing 100080,China 2 Graduate School of Chinese Academy of Sciences,Beijing 100039,China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Due to special properties of transient species, such as short-lived, unstable, reactive, and even explosive, the generation and subsequent characterization is a great challenge for experimental chemists. In our laboratory, systematic researches have been carried out to investigate novel transient species: reactive halogen species (RHS), short-lived free radicals, and metastable pseudohalogen compounds, based on the successive technical improvements on the Hel Photoelectron spectroscopy (PES). In this review, the topic mainly focuses on innovative methods of generating novel transient species, and subsequent geometric and electronic structure characterizations of these species combined with quantum chemical calculations.

关键词： reactive halogen species radicals pseudohalogen compounds Hel Photoelectron Spectroscopy (PES) quantum chemical calculations

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