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Introducing an Extended covalent bond between Oxygen Atoms with an OXO-Shape in Ions and Molecules: Compatibility with the Even-Odd and the Isoelectronicity Rules

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Open Journal of Physical Chemistry 2016年第3期6卷 67-77页

作者： Geoffroy Auvert Marine Auvert Grenoble Alpes University Grenoble France Strasbourg University Strasbourg France

Building on the recent success of the even-odd rule, the present paper explores its implications by studying the very specific case of OXO compounds. These compounds are usually represented with double bonds linking two oxygen atoms to a central atom—as in carbon dioxyde—yet can sometimes be drawn in a triangular structure, such as in calcium dioxyde. Measurement data moreover indicate that most OXO compounds have an angle around 120° between oxygen atoms, although that seems incompatible with triangular representations. The aim here is to unify these commonly admitted representations by linking oxygen atoms through a single bond that is longer than usual covalent bonds: an “elongated bond”. This elongated bond has the interesting effect of suppressing the need for double bonds between oxygen and the central atom. The elongated bond concept is applied to about a hundred of molecules and ions and methodically compared to classical representations. It is shown that this new representation, associated to the even-odd rule, is compatible with all studied compounds and can be used in place of their classical drawings. Its usage greatly simplifies complex concepts like resonance and separated charges in gases. Elongated bonds are also shown to be practicable with the isoelectronic rule as well as isomers, and throughout chemical reactions. This study of an especially long and wide angle bond confirms the versatility of the even-odd rule: it is not limited to compounds with short covalent bonds and can include OO covalent bond lengths of more than 200 pm and with OXO angles above 90°.

关键词： Elongated bond covalent bond Even-Odd Double bond Isoelectronicity Rules Chemistry Ions Molecule

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Biodegradation,hemocompatibility and covalent bonding mechanism of electrografting polyethylacrylate coating on Mg alloy for cardiovascular stent

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Journal of Materials Science & Technology 2020年第11期42卷 114-126页

作者： Yong-Xin Yang Zhe Fang Yi-Hao Liu Ya-Chen Hou Li-Guo Wang Yi-Fan Zhou Shi-Jie Zhu Rong-Chang Zeng Yu-Feng Zheng Shao-Kang Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001China Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou450002China Key Laboratory of Advanced Materials Processing&Mold Ministry of Education Zhengzhou450002China Corrosion Laboratory of Light Metals College of Material Science and EngineeringShandong University of Science and TechnologyQingdao266590China State Key Laboratory for Turbulence and Complex System and Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China

Organic coatings are the most widely employed approach for the promotion of corrosion resistance of magnesium(Mg)alloys.Unfortunately,traditional organic coatings are weakly bonded to Mg substrates due to physical adsorption.Herein,a polyethylacrylate(PEA)coating was fabricated on Mg-Zn-YNd alloy via electro-grafting.The surface structure and chemical composition were characterized by means of scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS),atomic force microscope(AFM)and Fourier transform infrared(FTIR)as well as time of flight-secondary ion mass spectrometer(To F-SIMS).The results showed that the surface roughness of PEA coating was dominated by scan rate;while the coverage and integrity of PEA coating were mainly affected by the monomer concentration and sweep circles.To F-SIMS results indicated that PEA coating was wholly covered on Mg alloy,and the presence of C2H3Mg-fragment confirmed the covalent bond between PEA coating and Mg alloy.In addition,DFT calculation results of the adsorption of EA molecules with Mg substrate agree well with the experimental phenomena and observation,suggesting that the electrons in 3s orbit of Mg atoms and 2pz orbit of C1 atom participated in the formation of covalent bond between PEA coating and Mg substrate.Potentiodynamic polarization curves and immersion test demonstrated that the PEA coatings could effectively enhance the corrosion resistance of Mg alloy.The platelet adhesion results designated that platelets were barely visible on PEA coating,which implied that PEA coating could effectively prevent the thrombosis and coagulation of platelets.PEA coating might be a promising candidate coating of Mg alloy for cardiovascular stent.

关键词： Magnesium alloy Organic coating Electro-grafting covalent bond Density functional theory Biomaterial

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covalent hadronic molecules induced by shared light quarks

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Communications in Theoretical Physics 2022年第12期74卷 62-86页

作者： Hua-Xing Chen School of Physics Southeast UniversityNanjing 210094China

After examining Feynman diagrams corresponding to the ■, ■, ■, and ■ hadronic molecular states, we propose a possible binding mechanism induced by shared light quarks. This mechanism is similar to the covalent bond in chemical molecules induced by shared electrons. We use the method of QCD sum rules to calculate its corresponding light-quark-exchange diagrams, and the obtained results indicate a model-independent hypothesis: the light-quark-exchange interaction is attractive when the shared light quarks are totally antisymmetric so they obey the Pauli principle. We build a toy model with four parameters to formulize this picture and estimate binding energies of some possibly-existing covalent hadronic molecules. A unique feature of this picture is that the binding energies of the(I)JP=(0)1+■ hadronic molecules are much larger than those of the (I)JP=(0)1+■ ones, while the(I)JP=(1/2)1/2+■ hadronic molecules have similar binding energies.

关键词： hadronic molecule covalent bond QCD sum rules

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具有共价键特征的金属-有机基团促进高性能钾离子电池

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Science China Materials 2023年第10期66卷 3827-3836页

作者：贾鑫鑫李胜阳陈嵩王磊邓弘立袁艺智孙洪涛符立才朱建鲁兵安 College of Materials Science and Engineering College of Chemistry and Chemical EngineeringCollege of Physics and ElectronicsHunan UniversityChangsha 410082China MOE Key Laboratory of Low-grade Energy Utilization Technologies and Systems School of Energy&Power EngineeringChongqing UniversityChongqing 400044China The Harold&Inge Marcus Department of Industrial&Manufacturing Engineering Materials Research Institute(MRI)The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

钾离子电池(PIBs)面临的一个关键问题是设计具有先进结构的负极材料,以实现快速电荷传输以提高钾的存储性能.采用碳二亚胺铁(FeNCN)作为阳极,由于其含有一定数量的共价键且在分子水平上具有稳定的结构,使得储钾系统能够实现优异的电化... 详细信息

钾离子电池(PIBs)面临的一个关键问题是设计具有先进结构的负极材料,以实现快速电荷传输以提高钾的存储性能.采用碳二亚胺铁(FeNCN)作为阳极,由于其含有一定数量的共价键且在分子水平上具有稳定的结构,使得储钾系统能够实现优异的电化学性能.FeNCN阳极具有高导电性,带隙接近0 eV,并且由于其共价键结构具有良好的结构稳定性.此外,无定形反应产物也为离子扩散提供了多种途径.因此,FeNCN阳极表现出高可逆比容量(在50 mA g^(-1)电流密度下具有600 mA h g^(-1)比容量),显著的倍率性能和长寿命循环(电流密度为500 mA g^(-1)时拥有400 mA h g^(-1)比容量且超过300次循环).通过理论模拟、X射线原位衍射分析和X射线光电子能谱分析揭示了Fe^(2+)和K^(+)之间的转化反应机理.此外,将FeNCN负极与苝-3,4,9,10-四羧酸二酐正极材料匹配,组装成的全电池在198.6 Wkg^(-1)的功率密度下实现了184.7 W h kg^(-1)的超高能量密度,明显高于以往所有铁基负极的PIBs或钾离子混合电容器.

关键词： potassium-ion batteries metal-organic group anodes covalent bond

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An effective method to generate controllable levels of ROS for the enhancement of HUVEC proliferation using a chlorin e6-immobilized PET film as a photo-functional biomaterial

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Regenerative Biomaterials 2021年第2期8卷 94-103页

作者： Seung Hee Hong Min-Ah Koo Mi Hee Lee Gyeung Mi Seon Ye Jin Park HaKyeong Jeong Dohyun Kim Jong-Chul Park Cellbiocontrol Laboratory Department of Medical Engineering Department of Medical Engineering Graduate School of Medical ScienceBrain Korea 21 Project Department of Medical Device Engineering and Management Yonsei UniversityCollege of MedicineSeoul 03722Republic of Korea

Reactive oxygen species(ROS)are byproducts of cellular metabolism;they play a significant role as secondary messengers in cell signaling.In cells,high concentrations of ROS induce apoptosis,senescence,and contact inhibition,while low concentrations of ROS result in angiogenesis,proliferation,and cytoskeleton remodeling.Thus,controlling ROS generation is an important factor in cell biology.We designed a chlorin e6(Ce6)-immobilized polyethylene terephthalate(PET)film(Ce6-PET)to produce extracellular ROS under red-light irradiation.The application of Ce6-PET films can regulate the generation of ROS by altering the intensity of light-emitting diode sources.We confirmed that the Ce6-PET film could effectively promote cell growth under irradiation at 500 μW/cm^(2) for 30 min in human umbilical vein endothelial cells.We also found that the Ce6-PET film is more efficient in generating ROS than a Ce6-incorporated polyurethane film under the same conditions.Ce6-PET fabrication shows promise for improving the localized delivery of extracellular ROS and regulating ROS formation through the optimization of irradiation intensity.

关键词： reactive oxygen species chlorin e6 dopamine covalent bond HUVEC proliferation

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Synthesis of covalently bonded reduced graphene oxide-Fe_(3)O_(4) nanocomposites for efficient electromagnetic wave absorption

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Journal of Materials Science & Technology 2021年第13期72卷 93-103页

作者： Xudong Liu Ying Huang Ling Ding Xiaoxiao Zhao Panbo Liu Tiehu Li MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China NPU-NCP Joint International Research Center on Advanced Nanomaterials&Defects Engineering State Key Laboratory of Solidification ProcessingShaanxi Engineering Laboratory for Graphene New Carbon Materials and ApplicationsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

High-performance electromagnetic(EM)wave absorbers,covalently bonded reduced graphene oxideFe_(3)O_(4) nanocomposites(rGO-Fe_(3)O_(4)),are synthesized via hydrothermal reaction,amidation reaction and reduction process.The microstructure,surface element composition and morphology of rGO-Fe_(3)O_(4) nanocomposites are characterized and corresponding EM wave absorption properties are analyzed in great detail.It demonstrates that Fe_(3)O_(4) nanoparticles are successfully covalently grafted onto graphene by amide bonds.When the mass ratio of rGO and Fe_(3)O_(4) is 2:1(sample S2),the absorber exhibits the excellent EM wave absorption performance that the maximum reflection loss(RL)reaches up to-48.6 dB at 14.4 GHz,while the effective absorption bandwidth(RLcovalent bonds considered to be carrier channels can facilitate electron migration,adjust EM parameters and then enhance EM wave absorption perfo rmance.This work provides a possible method for preparing efficient EM wave absorbers.

关键词： covalent bond EM wave absorption RCS simulation calculation rGO-Fe_(3)O_(4)nanocomposites

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Application of the TFD Model and Yu's Theory to Material Design

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Progress in Natural Science:Materials International 1993年第3期3卷 211-230页

作者：程开甲 Beijing 100037 Commission of Science Technology and Industry for National Defence PRC

An improved version of the TFD model is proposed to the effect that if correct boundaryconditions are adopted in the treatment of the EOS and heat of formation of metallic compounds,this modelpossesses a vast capability in giving a concrete description of behavior of electrons and all the specificparameters in any empirical electronic theory.It gives the calculated parameters of the electronic states in per-fect agreement with the data predicted by the Yu’s empirical electronic theory of metal.TFD model thuscan serve as a probe into the investigation of the theoretical aspects of the solid state physics and could helpdevising prescriptions for material designing.

关键词： TFD covalent bond EOS heat of formation material design

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Ultrasensitive and stable all graphene field-effect transistor-based Hg^(2+)sensor constructed by using different covalently bonded RGO films assembled by different conjugate linking molecules

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SmartMat 2021年第2期2卷 213-225页

作者： Mingyuan Sun Congcong Zhang Duo Chen Jian Wang Yanchen Ji Na Liang Haoyang Gao Shanshan Cheng Hong Liu Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong Institute for Advanced Interdisciplinary Research(iAIR)University of JinanJinanChina International School for Optoelectronic Engineering Qilu University of Technology(Shandong Academy of Science)JinanChina Department of Physics School of Physical Science and TechnologyUniversity of JinanJinanChina Department of Chemistry School of ScienceUniversity of TianjinTianjinChina State Key Laboratory of Crystal Materials Shandong UniversityJinanChina

As"molecular bridge,"coupling agents can not only realize the covalent connection of composites,but also affect their properties,thus affecting the properties of devices based on them.Herein,leveraging differences in charge conduction properties of the(3-aminopropyl)trimethoxysilane and 5,10,15,20-tetrakis(4-aminophenyl)-21H,23H-porphine caused by conjugacy structural differences,two kinds of layerby-layer assembled smart carbon materials with different electrical properties are obtained at the same reduction temperature.The two graphene ultrathin films are then“planted”on Si/SiO2 substrates,respectively,as semiconductor layer and source/drain electrodes to fabricate an ultra-stable all-graphene field effect transistor(AG-FET).Enabled by the covalent functionalized configuration and the functionally diverse of coupling agents,the AG-FET obtained by this simple method won the high electrical characteristics,the hole,electron mobility,and the shelflife could reach 3.79 cm2/(V·s),3.78 cm2/(V·s),and 18months,respectively.In addition,good material stability and excellent device structure endow the device exceptional stability,electrical stability,and solvent resistance,improving its application prospect in solution phase sensing/detection.Such characteristics could be used to sense,transduce,and respond to external stimuli,especially in solution phase to monitor the important analytes,such as Hg^(2+)in a flowing sewage environment.We believe that such easy-to-manufacture AG-FETs with ultrahigh performance and ultrahigh stability could also show great application prospects in other significant fields.

关键词： coupling agent covalent bond field effect transistors Hg^(2+)detection ultra-stable

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The Even-Odd and the Isoelectronicity Rules Applied to Single covalent bonds in Ionic, Double-Face-Centered Cubic and Diamond-Like Crystals

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Open Journal of Physical Chemistry 2016年第2期6卷 21-33页

作者： Geoffroy Auvert Marine Auvert Grenoble Alp University Grenoble France University of Strasbourg Strasbourg France

Although atom configuration in crystals is precisely known thanks to imaging techniques, there is no experimental way to know the exact location of bonds or charges. Many different representations have been proposed, yet no theory to unify conceptions. The present paper describes methods to derive bonds and charge location in double-face-centered cubic crystals with 4 and 6 atoms per unit cell using two novel rules introduced in earlier works: the even-odd and the isoelectronicity rules. Both of these rules were previously applied to ions, molecules and some solids, and the even-odd rule was also tested on two covalent crystal structures: centered-cubic and single-face-centered cubic crystals. In the present study, the diamond-like structure was subjected to the isoelectronicity rule in order to derive Zinc-blende structures. Rock-salt-like crystals were derived from each other using both rules. These structures represent together more than 230 different crystals. Findings for these structures are threefold: both rules describe a very sure method to obtain valid single covalent-bonded structures;single covalent structures can be used in every case instead of the classical ionic model;covalent bonds and charges positions do not have any relation with the valence number given in the periodic table.

关键词： covalent bond Even-Odd Rule Single bond Chemical Structure Crystal Solid Ionic Crystal Face-Centered Crystal Diamond-Like

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Effects of a donor on the bond property of quantum-dot molecules

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Chinese Physics B 2004年第6期13卷 942-947页

作者：王立民罗莹马本堃段素青赵宪庚 InstituteofAppliedPhysicsandComputationalMathematics Beijing100088China DepartmentofPhysicsandInstituteofTheoreticalPhysics BeijingNormalUniversityBeijing100875China

Within the framework of effective mass approximation, we have calculated the electronic structure of the two laterally coupled quantum dots with a donor by the finite element method. The calculated results show that the bond states of quantum-dot molecules are quite sensitive to the donor positions. By varying the donor position, the transition from covalent to ionic bond state is realized for some electronic states. Some extreme cases are also discussed for comparison.

关键词： covalent bond ionic bond wave function energy level

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