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Selective synthesis of the B_(11)H_(14)^(-) and B_(12)H_(12)^(2-) borane derivatives and the general mechanisms of the B-H bond condensation

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Science China Chemistry 2024年第3期67卷 876-881页

作者： Yi Jing Xinghua wang Hui Han Xin-Ran Liu Xing-Chao Yu Xi-Meng Chen Donghui Wei lai-sheng wang Xuenian Chen College of Chemistry Green Catalysis CenterZhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy MaterialsHenan Normal UniversityXinxiang 453007China Department of Chemistry Brown UniversityProvidenceRI 02912USA

Polyhedral boranes are a class of well-known boron molecular clusters with unique physical and chemical properties,and great efforts have been made in the past decades to find more effective synthetic ***,the established synthetic methods suffer from low efficiency and low selectivity because the mechanism of the B-H bond condensation reaction,critical for the synthesis of the polyhedral boranes,is not well *** we report highly selective and efficient synthetic methods of the salts of the tetradecahydridoundecaborate(1-)(B_(11)H^(-)_(14)) and dodecahydrido-dodecaborates(2-)(B_(12)H_(12)^(2-)) anions by employing commercially available and inexpensive starting *** theoretical and experimental investigations are carried out to elucidate the reaction *** have found that the nature of the B-H bond condensation is the dihydrogen bonding interaction in which the positively charged hydrogens(bridged hydrogens) play a crucial *** current study has not only led to more effective and selective synthetic methods for B_(11)H^(-)_(14) and B_(12)H_(12)^(2-) but also unveiled the nature of the B-H bond condensation and the general formation mechanisms of polyhedral *** finding will facilitate the development of more effective synthetic methods for polyhedral boranes and spur their wide application.

关键词： Boranes polyhedral boranes dihydrogen bond nucleophilicity

Preface to the Special Issue “ISSPIC XIX: International Symposium on Small Particles and Inorganic Clusters 2018”

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Chinese Journal of Chemical Physics 2019年第2期32卷 I0001-I0001页

作者： lai-sheng wang Min Han Department of Chemistry Brown University Providence Rhode Island 02912 USA National Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China

This Special Issue serves as the proceedings for the 19th International Symposium on Small Particles and In- organic Clusters (ISSPIC XIX), held in Hangzhou, China from August 12-17, 2018. All the articles represent o... 详细信息

关键词： Special Issue serves International Symposium articles represent

Cryogenic Photodetachment Spectroscopy and High-Resolution Resonant Photoelectron Imaging of Cold para-Ethylphenolate Anions

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Precision Chemistry 2023年第3期1卷 161-174页

作者： Dao-Fu Yuan Yue-Rou Zhang Chen-Hui Qian Guo-Zhu Zhu lai-sheng wang Department of Chemistry Brown UniversityProvidenceRhode Island 02912United States

Valence-bound molecular anions with polar neutral cores(μ>2.5 D)can support highly diffuse dipole-bound states(DBSs)as electronically excited states just below the detachment *** weakly bound nonvalence excited states have little influence on the structure of the neutral core,and they usually have the same vibrational *** can be systematically searched using photodetachment spectroscopy(PDS),which can yield the binding energies of the DBSs,the electron detachment threshold of the anion,and above-threshold vibrational levels of the DBSs(Feshbach resonances).We have shown that the combination of PDS and resonant photoelectron spectroscopy(rPES)at the Feshbach resonances is a powerful approach to obtain rich vibrational information for complex molecular radicals.A prerequisite for this technique is to produce vibrationally cold anions,made possible by a cryogenically controlled Paul *** this article,we report a PDS and rPES study of cold para-ethylphenolate anions(p-EP^(-)).The electron affinity of the p-EP radical is measured to be 17425±3 cm^(-1)(2.1604±0.0004 eV),and a DBS is found at 145 cm^(-1) below the detachment threshold of p-EP^(-).Thirty-four vibrational levels are observed for the DBS,including two bound levels and 32 Feshbach *** for 17 vibrational modes of the p-EP radical are measured from the combination of PDS and rPES,including six symmetry-forbidden modes with A″*** current study confirms again the power of combining cryogenic ion cooling with PDS and highresolution rPES to obtain spectroscopic information on complex molecular radicals.

关键词： dipole-bound state photoelectron imaging cryogenic ion cooling resonant photoelectron spectroscopy ethylphenoxy radical vibrational frequencies electrospray ionization

Bond-bending isomerism of Au2I3-: competition betweenaurophilicityand covalent bonding

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Bond-bending isomerism of Au2I3-: competition betweenaurophi...

第七届全国物理无机化学学术会议

作者： Wan-Lu Li Tian Jian lai-sheng wang Jun Li Department of Chemistry Tsinghua University Department of Chemistry Brown University

Herewe report a joint photoelectron spectroscopy and theoretical investigation of the gaseous AuIcluster,which is found to exhibit two types of isomers due to competition between Au–I covalent bonding and Au–Au aurophilic *** covalent bonding prefers a bent IAu IAuI structure with an obtuse Au-I-Au angle(100.7°),while aurophilic interactions pull two Au atoms much closer,leading to an

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水平管降膜蒸发器管外液膜铺展数值分析

石油化工设备 2019年第5期48卷 19-27页

作者：来盛旺李庆生南京工业大学机械与动力工程学院

运用FLUENT软件对水平管降膜蒸发器管外液膜的铺展过程进行数值模拟,分析了流量、管间距、管径及流体温度对水平管外液膜铺展的影响。模拟研究结果表明,液膜在水平管外分布不均匀,液膜铺展呈现波峰-平稳-波峰的周期性规律。在整个铺展... 详细信息

运用FLUENT软件对水平管降膜蒸发器管外液膜的铺展过程进行数值模拟,分析了流量、管间距、管径及流体温度对水平管外液膜铺展的影响。模拟研究结果表明,液膜在水平管外分布不均匀,液膜铺展呈现波峰-平稳-波峰的周期性规律。在整个铺展区域内液膜厚度随流体体积流量的增大而增大,随流体温度的增大而减小;在叠加区内液膜厚度随着管间距的增大而增大;在平稳区域和冲击区域内液膜厚度随着管间距的增大而减小。周向角θ为45°时,液膜厚度在叠加区随管径的增大而增大;周向角θ为90°、135°时,液膜厚度在整个铺展区域内随管间距的增大而减小。

关键词：降膜蒸发器水平换热管液膜铺展数值分析

Effect of diaminocyclohexane tetra-acetic acid on rapid growth and optical performances of potassium dihydrogen phosphate crystals

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Effect of diaminocyclohexane tetra-acetic acid on rapid grow...

第十六届全国晶体生长与材料学术会议

作者： sheng-Jun ZHU sheng-lai wang Jian-xu Ding Guang-Xia LIU Wen-Jie LIU State Key Laboratory of Crystal Materials and Institute of Crystal Materials Shandong University

By altering the concentration of diaminocyclohexane tetra-acetic acid(DCTA)additive in the growth solution,a series of potassium dihydrogen phosphate(KDP)crystals were obtained at growth rate of 10-15mm/day by the"point seed"rapid growth *** measurement result of laser polarization interference showd that,with increasing the concentration of DCTA,the growth critical supersaturationσ(dead zone)for(100)face of KDP crystals was decreased continually,while the growth rate for(100)face of KDP crystals was firstly increased and then decreased,passing through a *** amount of DCTA doped enhanced the stability of growth solution,increased the UV transmittance and the laser damage threshold,and reduced the light scattering of rapidly grown KDP crystals,which is benefit to improve the rapid growth and optical quality of KDP ***,1 excess addition of DCTA had the adverse *** effect of DCTA on the rapid growth and optical properties of KDP crystals is attributed to the chelation of DCTA with impurity metal ions and adsorption of DCTA molecules onto the face of KDP crystals.

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Boronyl Chemistry: Terminal μ~1-BO,Bridging μ~2-BO,and Face-Capping μ~3-BO as New Ligands in Gas-Phase Clusters

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Boronyl Chemistry: Terminal μ~1-BO,Bridging μ~2-BO,and Fac...

中国化学会第十二届全国量子化学会议

作者： Hua-Jin Zhai Qiang Chen Hui Bai Si-Dian Li lai-sheng wang Institute of Molecular Science Shanxi University Department of Chemistry Brown University

Concerted experimental and theoretical investigations have confirmed that boronyl group （BO）,which is isovalent to CN and CO,is a monovalent σ radical with a robust BoO triple *** the basis of BO/Au/H isolobal analogy,we have successfully produced and characterized various gas-phase clusters with μn-BO groups （n=1,2,3）,including terminal m1-BO in linear B（BO）2-/0 and B2（BO）22-/-/0,triangular B（BO）3-/0,tetrahedral B（BO）4-,planar B3（BO）n- （n=1,2）,B4（BO）n- （n=1-3）,B10（BO）- and B12（BO）-,double-chain nanoribbon Bn（BO）2-/0 with p plus s double conjugation,and metal boronyl clusters Aun（BO）- and Aun（BO）（n = 1-3）1,bridging m2-BO in planar B2（BO）3- and B3（BO）3-,and face-capping m3-BO in octahedral B6（BO）7-2,***,the perfectly planar boronyl boroxine D3h B3O3（BO）3 with three m1-BO terminals appears to be a new member of the "inorganic benzene" family,while the newly reported B3On-/0/+ clusters （n = 2-4）3 possess novel 3c-2e ω-bonds and rhombic 4c-2e ο-*** to BO,BS group can also serve as effective terminal4 and bridging *** short,parallel to CN,the mn-BO and mn-BS （n=1,2,3） groups enrich the chemistry of boron and open the area of boronyl chemistry.

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Boronyl Chemistry: From Terminal μ~1-BO, to Bridging μ~2-BO, to Face-Capping μ~3-BO

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Boronyl Chemistry: From Terminal μ~1-BO, to Bridging μ~2-B...

中国化学会第29届学术年会

作者： Hua-Jin Zhai Qiang Chen Hui Bai Si-Dian Li lai-sheng wang Institute of Molecular Science Shanxi University Department of Chemistry Brown University

Joint experimental and theoretical studies have confirmed that the boronyl group（BO）is a monovalentσradical with a robust B=O triple bond,where BO/BO- are isovalent to CN/CN- and *** the basis of the BO/Au/H isolobal analogy,we have successfully produced and characterized a variety of gas-phase clusters with μn-BO groups（n=1,2,3）.These include terminal μ1-BO in linear B（BO）21/0 and B2（BO）22-/-/0,triangular B（BO）3-/0,tetrahedral B（BO）4-,planar B3（BO）n-（n=1,2）,B4（BO）n-（n=1-3）,B10（BO）- and B12（BO）-,double-cha in nanoribbon Bn（BO）2-/0 with π plus σ double conjugation,and metal boronyl clusters Aun（BO）- and Aun（BO）（n=1-3）1,bridging μ2-BO in planar B2（BO）3- and B3（BO）3 and face-capping 3-BO in octahedral B6（BO）7- ***,the perfectly planar boronyl boroxine D3h B3O3（BO）3 with three 1-BO terminals represents a new member of the"inorganic benzene"family,while the newly reported B3On-/0/+clusters（n=2-4）3 possess novel3c-2eω-bonds and rhombic 4c-2eο-*** to BO,the BS group can also serve as effective terminal4 and bridging *** short,parallel to CN,the μn-BO and μn-BS（n=1,2,3）groups enrich the chemistry of boron and open the area of boronyl chemistry.

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Probing the Electronic Structure of the CoB16- Drum Complex: Unusual Oxidation State of Co-1

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Chinese Journal of Chemical Physics 2019年第2期32卷 241-247,I0003页

作者： Wan-Lu Li Wan-Lu Lia Zhi-Yu Jiang Wei-Jia Chen Han-Shi Hu lai-sheng wang Jun Li Probing the Electronic Structure of the CoB16- Drum Complex: Unusual Oxidation State of Co-1 Probing the Electronic Structure of the CoB16- Drum Complex: Unusual Oxidation State of Co-1

Since the discovery of the first drum-like CoB16- complex, metal-doped drum-like boron nanotubular structures have been investigated with various metal dopants and different tubular size, forming a new class of novel nanostructures. The CoB16- cluster was found to be composed of a central Co atom coordinated by two fused B8 rings in a tubular structure, representing the potential embryo of metal-filled boron nanotubes and providing opportunities to design one-dimensional metal-boron nanostructures. Here we report improved photoelectron spectroscopy and a more in-depth electronic structure analysis of CoB16-, providing further insight into the chemical bonding and stability of the drum-like doped boron tubular structures. Most interestingly, we find that the central Co atom has an unusually low oxidation state of ?1 and neutral CoB16 can be viewed as a charge transfer complex (Co-@BB16+), suggesting both covalent and electrostatic interactions between the dopant and the boron drum.

关键词： Photoelectron spectroscopy Metal-boron clusters Ab initio calculations Chemical bonding