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Understanding Bonding Nature ofα-keggin Polyoxometalates[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S):A Generalized Superatomic Perspective

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Energy & Environmental Materials 2024年第6期7卷 176-183页

作者： Rui Li Yulei Shi Famin Yu Rui Wang Haitao Yan Boon k.teo Zhigang Wang Department of Physics Capital Normal UniversityBeijing 100048China key Laboratory of Material Simulation Methods&Software of Ministry of Education College of PhysicsJilin UniversityChangchun 130012China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China State key Laboratory for Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Institute of Theoretical Chemistry College of ChemistryJilin UniversityChangchun 130012China

α-keggin polyoxometalates(POMs)[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S)are widely used in batteries owing to their remarkable redox ***,the mechanism underlying the applications appears inconsistent with the widely accepted covalent bonding ***,first-principles calculations show that XW_(12)are core–shell structures composed of a shell and an XO_(4)^(n−)core,both are stabilized by covalent ***,owing to the presence of a substantial number of electrons in W_(12)O_(36)shell,the frontier molecular orbitals of XW_(12)are not only strongly delocalized but also exhibit superatomic properties with high-angular momentum electrons that do not conform to the Jellium *** analysis indicates that energetically high lying filled molecular orbitals(MOs)have reached unusually high-angular momentum characterized by quantum number k or higher,allowing for the accommodation of numerous *** attribute confers strong electron acceptor ability and redox activity to XW_(12).Moreover,electrons added to XW_(12)still occupy the k orbitals and will not cause rearrangement of the MOs,thereby maintaining the stability of these *** findings highlight the structure–activity relationship and provide a direction for tailor-made POMs with specific properties at atomic level.

关键词： first principles molecular orbital polyoxometalate redox activity superatom

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Chirality recognition in concerted proton transfer process for prismatic water clusters

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Nano Research 2016年第9期9卷 2782-2795页

作者： Bo Wang Wanrun Jiang Yang Gao Boon k.teo Zhigang Wang Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Jilin Provincial key Laboratory of Applied Atomic and Molecular Spectroscopy(Jilin University) Changchun 130012China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China Beijing Computational Science Research Center Beijing 100084China

Proton transfer and chiral conversion via hydrogen bonds (HBs) are important processes in applications such as chiral recognition, enzymatic catalysis, and drug preparation. Herein, we investigate the chiral conversion and interlayer recognition, via concerted intralayer proton transfer (CIPT) processes, of small prismatic water clusters, in the form of bilayer n−membered water rings (BnWRs, n = 4, 5, 6). Density functional theory (DFT) calculations show that despite the small energy variations between the initial and final states of the clusters of less than 0.3 kcal·mol−1, the vibrational circular dichroism (VCD) spectrum provides clear chiral recognition peaks in the range of 3,000 to 3,500 cm−1. The vibrational modes in this region correspond to stretching of intralayer HBs, which produces strong signals in the infrared (IR) and Raman spectra. The electronic circular dichroism (ECD) spectrum also reveals obvious chiroptical characteristics. The molecular orbitals involved in the interlayer interaction are dominated by O 2p atomic orbitals; the energy of these orbitals increased by up to 0.1 eV as a result of the CIPT processes, indicating corresponding recognition between monolayer water clusters. In addition, isotopic substitution by deuterium in the BnWRs results in characteristic peaks in the VCD spectra that can be used as fingerprints in the identification of the chiral structures. Our findings provide new insights into the mechanism of chiral recognition in small prismatic water clusters at the atomic level as well as incentives for future experimental studies. [Figure not available: see fulltext.] © 2016, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

关键词： water cluster chirality proton transfer circular dichroism spectrum density functional theory calculation

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Actinide-embedded gold superatom models： Electronic structure, spectroscopic properties, and applications in surface-enhanced Raman scattering

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Nano Research 2016年第3期9卷 622-632页

作者： Yang Gao Bo Wang Yanyu Lei Boon k. teo Zhigang Wang Institute of Atomic and Molecular Physics Jilin University Changchun 130012 China Jilin Provincial key Laboratory of AppliedAtomic and Molecular Spectroscopy Jilin University Changchun 130012 China College of Chemistry and Molecular Engineering Peking University Beijing 100871 China College of Chemistry and Chemical Engineering Kiamen University Xiamen 361005 China Beijing Computational Science Research Center Beijing 100084 China

Actinide elements encaged in a superatomic cluster can exhibit unique properties due to their hyperactive valence electrons. Herein, the electronic and spectroscopic properties of Th@Au14 are predicted and compared with that of the isoelectronic entities [Ac@Au14]- and [Pa@Au14]＋ using density functional theory. The calculation results indicate that these clusters all adopt a closed- shell superatomic 18-electron configuration of the 1S21p61D10 Jellium state. The absorption spectrum of Th@Au14 can be interpreted by the Jelliumatic orbital model. In addition, calculated spectra of pyridine-Th@Au14 complexes in the blue laser band exhibit strong peaks attributable to charge transfer （CT） from the metal to the pyridine molecule. These charge-transfer bands lead to a resonant surface-enhanced Raman scattering （SERS） enhancement of -104. This work suggests a basis for designing and synthesizing SERS substrate materials based on actinide-embedded gold superatom models.

关键词： actinide element DFT calculation gold nanoparticle superatomic orbital surface-enhanced Ramanscattering

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Superatomic Aub clusters ligated by different N-heterocyclic carbenes and their ligand-dependent catalysis, photoluminescence, and proton sensitivity

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Nano Research 2020年第7期13卷 1908-1911页

作者： Hui Shen Sijin Xiang Zhen Xu Chen Liu Xihua Li Cunfa Sun Shuichao Lin Boon k.teo Nanfeng Zheng State key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsNational&Local Joint Engineering Research Center of Preparation Technology of NanomaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China School of Pharmaceutical Science Xiamen UniversityXiamen 361002China

We report herein a class of superatomic AU13 clusters stabilized by different N-heterocyclic carbenes(NHCs).The clusters show diverse metal surface structures,properties and functions as exemplified by:(1)the first anionic AU13 cluster[Au1g(NHC-1)sBr6],which has bulky NHC-1 ligands that lead to a rather open metal surface contributing to its high catalytic activity;(2)the tricationic cluster[Au13(NHC-2)sBr2]+which has bidentate,benzyl-rich NHC-2 ligands that make it ultra-stable and highly-luminescent,suitable for bio-imaging;and(3)by bearing two pyridyl groups on NHC-3,the dicationic cluster[Au:a(NHC-3)gClg]f+exhibits reversible and stable visible absorption and solubility responses to protonation/deprotonation cycles,making it a potential pH sensor(NHC-1=1,3-disopropylbenzimidazolin-ylidene;NHC-2=1,3-bis(1-benzyl-1H-benzimidazol-1-ium-yl)propane;NHC-3=1,3-bis(icolyI)benzimidazolin-ylidene).The study nicely demonstrates the importance of ligands in designing metal nanoclusters with desired functionalities.

关键词： carbene ligands gold nanocluster catalysis luminescenee Au13

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过渡金属银配体簇化合物的质谱分析

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分析化学 2001年第3期29卷 280-282页

作者：胡长风欧阳荔彭嘉柔 Yihui Xu Boon.k.teo Department of Chemistry!University of Illinoisat Chicago IL 60607.USA 北京大学医药卫生分析中心!北京100083

用基质辅助激光解吸电离飞行时间质谱 (MALDI TOF MS)测定含有过渡金属银配位的簇类化合物苯乙炔基银的结构及其聚合度 ,比较了线性 (linear)和反射 (reflectron)飞行时间质谱各自的特点 ,探讨了银10 7Ag、10 9Ag两种同位素在质谱中的... 详细信息

用基质辅助激光解吸电离飞行时间质谱 (MALDI TOF MS)测定含有过渡金属银配位的簇类化合物苯乙炔基银的结构及其聚合度 ,比较了线性 (linear)和反射 (reflectron)飞行时间质谱各自的特点 ,探讨了银10 7Ag、10 9Ag两种同位素在质谱中的贡献及其表现。

关键词：基质辅助激光解吸电离飞行时间质谱簇类化合物银同位素

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Thiol-stabilized atomically precise, superatomic silver nanoparticles for catalysing cycloisomerization of alkynyl amines

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National Science Review 2018年第5期5卷 694-702页

作者： Juanzhu Yan Jun Zhang Xumao Chen Sami Malola Bo Zhou Elli Selenius Xiaomin Zhang Peng Yuan Guocheng Deng kunlong Liu Haifeng Su Boon k.teo Hannu Hkkinen Lansun Zheng Nanfeng Zheng State key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Engineering Research Center for Nano-Preparation Technology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen University School of Materials and Chemical Engineering Anhui Jianzhu University Departments of Physics and Chemistry Nanoscience CenterUniversity of Jyvskyl

Both the electronic and surface structures of metal nanomaterials play critical roles in determining their chemical properties. However, the non-molecular nature of conventional nanoparticles makes it extremely challenging to understand the molecular mechanism behind many of their unique electronic and surface properties. In this work, we report the synthesis, molecular and electronic structures of an atomically precise nanoparticle, [Ag206 L72]~q(L = thiolate, halide; q = charge). With a four-shell Ag7@Ag32@Ag77@Ag90 Ino-decahedral structure having a nearly perfect D5hsymmetry, the metal core of the nanoparticle is co-stabilized by 68 thiolate and 4 halide ligands. Both electrochemistry and plasmonic absorption reveal the metallic nature of the nanoparticles, which is explained by density functional theory ***, the nanoparticle can be considered as a superatom, just short of a major electron shell closing of 138 electrons(q = –4). More importantly, many of ligands capping on the nanoparticle are labile due to their low-coordination modes, leading to high surface reactivity for catalysing the synthesis of indoles from 2-ethynylaniline derivatives. The results exemplify the power of the atomic-precision nanocluster approach to catalysis in probing reaction mechanisms and in revealing the interplay of heterogeneous reactivities,electronic and surface structural dynamics, thereby providing ways for optimization.

关键词： metal nanoclusters atomically precise nanoparticles nobel metal superatom nanocatalysis

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Telmisartan, ramipril, or both in high-risk Chinese patients： analysis of ONTARGET China data

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Chinese Medical Journal 2011年第12期000卷 1763-1768页

作者： YU Li-tian ZHU Jun TAN Hui-qiong WANG Guo-gan koon k. teo LIU Li-sheng Emergency Center Cardiovascular Institute and Fuwai Hospital Peking Union Medical College and Chinese Academy ofMedical Sciences Beijing 100037 China Hypertension Center Cardiovascular Institute and Fuwai Hospital Peking Union Medical College and Chinese Academy ofMedical Sciences Beijing 100037 China Population Health Research Institute McMaster University andHamilton Health Sciences Hamilton ON Canada

Background The results from the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial （ONTARGET） indicated that the angiotensin-receptor blocker telmisartan was not inferior to the angiotensin-converting-enzyme inhibitor ramipril in reducing the composite endpoint of cardiovascular death, myocardial infarction, stroke or hospitalization for congestive heart failure in high-risk patients, and telmisartan was associated with slightly superior tolerability. The combination of the two drugs was associated with more adverse events without an increase in benefit. This study aimed to analyze the data from ONTARGET obtained from a subgroup of patients enrolled in China and to evaluate the demographic and baseline characteristics, the compliance, efficacy, and safety of the different treatment strategies in randomized patients in China. Methods A total of 1159 high-risk patients were randomized into three treatment groups： with 390 assigned to receive 80 mg of telmisartan, 385 assigned to receive 10 mg of ramipril and 384 assigned to receive both study medications. The median follow-up period was 4.3 years. Results The mean age of Chinese patients was 65.6 years, 73.6% of patients were male. The proportion of patients with stroke/transient ischemic attacks at baseline in China was two times more than the entire study population （47.7% vs 20.9%）. In Chinese patients the proportion of permanent discontinuation of study medication due to cough was 0.5% in the telmisartan group, which was much less than that in the combination or the ramipril group. There were no significant differences in the incidence of primary outcome among three treatment groups of Chinese patients. More strokes occurred in Chinese patients than in the entire study population （8.5% vs. 4.5%）. Greater systolic blood pressure reduction （-9.8 mmHg）, and more renal function failure were noted in the combination treatment group than in the ramipril or telmisartan group （2.6% vs. 1.6% a

关键词： telmisartan ramipril, high-risk

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Aggregation-induced emission polymers via reversible-deactivation radical polymerization Special Collection:Distinguished Australian Researchers

Aggregate

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Aggregate 2024年第1期5卷 16-46页

作者： Nicholas kai Shiang teo Bo Fan Aditya Ardana San H.Thang School of Chemistry Monash UniversityClaytonVictoriaAustralia

Aggregation-induced emission(AIE)is a unique phenomenon whereby aggregation of molecules induces fluorescence emission as opposed to the more commonly known aggregation-caused quenching(ACQ).AIE has the potential to be utilized in the large-scale production of AIE-active polymeric materials because of their wide range of practical applications such as stimuli-responsive sensors,biological imaging agents,and drug delivery *** is evident from the increasing number of publications over the years since AIE was first *** addition,the evergrowing interest in this field has led many researchers around the world to develop new and creative methods in the design of monomers,initiators and crosslinkers,with the goal of broadening the scope and utility of AIE *** of the most promising approaches to the design and synthesis of AIE polymers is the use of the reversible-deactivation radical polymerization(RDRP)techniques,which enabled the production of well-controlled AIE materials that are often difficult to achieve by other *** this review,a summary of some recent works that utilize RDRP for AIE polymer design and synthesis is presented,including(i)the design of AIE-related monomers,initiators/crosslinkers;the achievements in preparation of AIE polymers using(ii)reversible addition–fragmentation chain transfer(RAFT)technique;(iii)atom transfer radical polymerization(ATRP)technique;(iv)other techniques such as Cu(0)-RDRP technique and nitroxide-mediated polymerization(NMP)technique;(v)the possible applications of these AIE polymers,and finally(vi)a summary/perspective and the future direction of AIE polymers.

关键词： aggregation-induced emission atom transfer radical polymerization nitroxide-mediated polymerization reversible addition–fragmentation chain transfer reversible-deactivation radical polymerization

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心脏病学的最新进展

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英国医学杂志中文版 1998年第3期1卷 130-134页

作者： koon k teo 俞梦越 EPICORE Centre Division of CardiologyDepartment of MedicineUniversity of AlbertaEdmontonAlbertaCanada T6G 2B7 associate professor of medicine

对急性缺血综合征、慢性冠状动脉性心脏病、充血性心力衰竭以及心源性猝死的研究已取得重要进展。此文着重综述心脏病学的这些进展及其临床应用。方法本文所用资料出自己发表的文献和同行们正在进行的临床试验。

关键词：充血性心力衰竭心脏病学心源性猝死支架治疗临床试验急性心肌梗塞受体阻滞剂急性缺血降脂治疗冠状动脉成形术

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Will Sustainable Food Sovereignty Research Be Sustainable in the Future?

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Agricultural Sciences 2024年第1期15卷 165-186页

作者： Teck Choon teo School of Business TMC Institute Tashkent Uzbekistan

The article proposes two agricultural paradigms to address global food production sustainability. First, precision agroecology may unite production-oriented and ecological agriculture, but it offers distinct solutions based on data, innovation, and decision-analysis technologies. The author demonstrates how precision technology and agroecological principles can transform agriculture by 1) minimizing inputs with optimization prescriptions, 2) replacing self-sustaining inputs with location variable rate technology, 3) integrating functional ecosystems into agroecosystems with exact preservation technology, 4) hooking up farmers and consumers via value-based food ecosystems, and 5) establishing equitable agroecology. Hence, precision agroecology provides a rare opportunity to integrate indigenous practices and contemporary technologies to revolutionize farming practices. Precision agroecology can tackle agriculture’s most serious sustainability issues in a world in flux.

关键词： Precision Agriculture Agroecology Biodiversity Food Systems

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