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Metastability of π-π stacking between the closed-shell ions of like charges

Chinese Journal of Structural Chemistry 2024年第5期43卷 22-29页

作者： Jiayao Li Xinru Peng Shiwei Yin Changwei Wang yirong mo Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi'an710119China Department of Nanoscience Joint School of Nanoscience&NanoengineeringUniversity of North Carolina at GreensboroGreensboroNC 27401USA

Planar cations or anions can form stacks in crystals or solutions,where the surrounding or environment plays a decisive role as demonstrated in previous ***,it remains unclear whether these counterintuitive interactions possess any inherent stability or are thoroughly repulsive if the constraint of environment is *** this work,we explored the inherent stability ofπ-πstacking between closed-shell ions of like charges with prototypes derived from experimental *** inherent metastability was identified by the characteristic local minima and the transition states preventing their dissociation and verified by ab initio molecular dynamics(AIMD)*** nature of involved interactions was deciphered with the energy decomposition approach based on the block-localized wavefunction method(BLW-ED).Like the conventional neutralπ-πstacking interactions,electron correlation is the most attractive energy *** it is overturned by the Coulombic repulsion between net charges for all modes of dimerization,resulting in the overall repulsive inter-cation or anion *** from van der Waals interactions were also observed in the reduced density gradient *** origin of the metastability was elucidated by examining the contributions of individual physical factors to the *** inherent metastability originates from the electron correlation,which dramatically increases due to the enhanced overlap between ions from a transition state to its corresponding minimum.

关键词： π-πstacking interactions Metastability Valence bond theory Energy decomposition analysis Electron correlation

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Strength of Intramolecular Hydrogen Bonds

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物理化学学报 2018年第3期34卷 278-285页

作者： JIANG Xiaoyu WU Wei mo yirong College of Ecological Environment and Urban Construction Fujian University of Technology The State Key Laboratory of Physical Chemistry of Solid Surfaces iChEM Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry and College of Chemistry and Chemical Engineering Xiamen University Department of Chemistry Western Michigan University

The concept of resonance-assisted hydrogen bonds(RAHBs)highlights the synergistic interplay between theπ-resonance and hydrogen bonding *** concept has been well-accepted in academia and is widely used in ***,it has been argued that the seemingly enhanced intramolecular hydrogen bonding(IMHB)in unsaturated compounds may simply be a result of the constraints imposed by theσ-skeleton ***,it is crucial to estimate the strength of *** this work,we used two approaches to probe the resonance effect and estimate the strength of the IMHBs in the two exemplary cases of the enol forms of acetylacetone and *** approach is the block-localized wavefunction(BLW)method,which is a variant of the ab initio valence bond(VB)*** this approach,it is possible to derive the geometries and energetics with resonance shut *** other approach is Edmiston’s truncated localized molecular orbital(TLmo)technique,which monitors the energy changes by removing the delocalization tails from localized molecular *** integrated BLW and TLmo studies confirmed that the hydrogen bonding in these two molecules is indeed enhanced byπ-resonance,and that this enhancement is not a result ofσconstraints.

关键词： Resonance-assisted hydrogen bond Bond strength Valence bond Block-localized wavefunction Truncated localized molecular orbital

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Intermolecular Interaction Analysis: Blue-Shifting Hydrogen Bonds and σ-Hole Halogen Bonds

Intermolecular Interaction Analysis: Blue-Shifting Hydrogen ...

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中国化学会第十二届全国量子化学会议

作者： yirong mo Department of Chemistry Western Michigan University Kalamazoo

Non-covalent（Y:…X-Z）interactions refer to the bonding without the direct involvement of electrons sharing between interacting *** though individual non-covalent interaction is weak,the accumulation of many non-covalent interaction leads to a significant force in the formation and function of super-molecules,maintain or folding/unfolding of protein and DNA structures,and rational design of self-assembling materials and *** have developed the block-localized wavefunction based energy decomposition（BLW-ED）approach to probe the nature of intermolecular *** this talk,I will focus on two issues related to the non-covalent interactions with BLW-ED analyses,namely the blue-shifting hydrogen bonding and theσ-hole *** deriving the energetic,geometrical and spectral changes with the deactivation of electron transfer（hyperconjugation）effect,we studied a series of H-bonding systems exhibiting both redand blue-shifting *** detailed analyses show that blue-shifting is a long-range *** among the various energy components contributing to hydrogen bonds,only the electrostatic interaction is of long-range characteristics,we conclude that the contraction and blue-shifting of a hydrogen bond is caused by the electrostatic *** the lengthening and red-shifting is primarily due to the short-range n（Y）→σ*（H-Z）*** competition between these two opposing factors determines the final frequency change direction.?-hole is a recent concept introduced by Politzer et *** showed that although a halogen atom（X=F,Cl,Br）carries partial negative charge,still the halogen has a region of positive electrostatic potential at the head of its lone pair and in the opposite direction of X-Z *** existence of σ holes implies that in halogen bonds,the electrostatic attraction is as directional as the electron transfer *** has also been proposed that the high directionality of halogen bonds compared with H-bonds is d

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The Role of Resonance and the Strength of Intramolecular Hydrogen Bonds（IMHBs）

The Role of Resonance and the Strength of Intramolecular Hyd...

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第十三届全国量子化学会议

作者： yirong mo Department of Chemistry Western Michigan University

＜正＞As one of the most fundamental concepts in chemistry, biology and material science,hydrogen bond （H-bond） has been extensively studied experimentally and theoretically. It ubiquitously exists among molecules （intermolecularly） or within a single molecule（intramolecularly）. One kind of prominent examples for the intramolecular H-bond （IMHB） is nucleic acids where H-bonding interactions among base pairs dominate the three-dimensional

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The Combined Effect of the Repulsion and Conjugation in Tautomerism of Protonated Imidazoles

The Combined Effect of the Repulsion and Conjugation in Taut...

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第十三届全国量子化学会议

作者： Huaiyu Zhang Wei Wu yirong mo The State Key Laboratory of Physical Chemistry of Solid Surfaces iChEMFujian Provincial Key Laboratory of Theoretical and Computational Chemistryand College of Chemistry and Chemical EngineeringXiamen University Department of Chemistry Western Michigan University

＜正＞Compared with the NH tautomers, the CH tautomers of imidazole and its derivatives have been little investigated due to the absence of aromaticity. But most recently, the4H-2,5diamino-imidazolium has been found by experiments.1-3 To examine the substituent effect, DFT and block-localized wave function （BLW） calculations concerning the resonance energies, the harmonic oscillator model of aromaticity

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块定域波函数方法及其应用

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化学学报 2000年第2期58卷 218-221页

作者：莫亦荣林梦海吴玮张乾二厦门大学化学系

提出了块定域波函数方法以定量分析分子内的电子定域现象或分子间的电荷传递效应.对于一个假想的严格定域的分子,我们通过将全部的电子和基轨道配分成几个子空间来构造其相应的波函数.其中每一个分子轨道只对某一个子空间展开,各子空间... 详细信息

提出了块定域波函数方法以定量分析分子内的电子定域现象或分子间的电荷传递效应.对于一个假想的严格定域的分子,我们通过将全部的电子和基轨道配分成几个子空间来构造其相应的波函数.其中每一个分子轨道只对某一个子空间展开,各子空间内的分子轨道相互正交,但不同子空间内的分子轨道间是非正交的.Hartree-Fock波函数和块定域波函数之间的能量之差即为分子内的电子定域能或分子间的电荷传递能.我们应用块定域波函数方法讨论了丁二烯分子中的旋转势垒.

关键词：电子离域块定域波函数丁二烯共轭超共轭

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AuCu团簇分子动力学研究

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厦门大学学报（自然科学版） 1999年第6期38卷 859-864页

作者：谭凯林梦海莫亦荣张乾二厦门大学化学系

根据D-B的嵌入原子法(EAM), 结合Johnson 双体势和Murrell多体势,对AuCu 团簇结构进行了分子动力学模拟.研究表明EAM 势函数可较好地描述非晶态合金体系.非晶态团簇形成中以多面体方式生长,无序态(采用二十面体及十面体结构)比有序态更... 详细信息

根据D-B的嵌入原子法(EAM), 结合Johnson 双体势和Murrell多体势,对AuCu 团簇结构进行了分子动力学模拟.研究表明EAM 势函数可较好地描述非晶态合金体系.非晶态团簇形成中以多面体方式生长,无序态(采用二十面体及十面体结构)比有序态更稳定.

关键词： AuCu团簇分子动力学模拟原子团簇金铜合金

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Ni_xZr_y(x:y=1∶2或2∶1)团簇的量子化学研究

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Chinese Journal of Chemical Physics 2001年第2期14卷 163-170页

作者：董昆明王艺平林梦海莫亦荣吴玮张乾二厦门大学化学系

根据化学键理论和拓扑学原理 ,设计了非晶态团簇NixZry(x :y =1∶2或 2∶1,x +y≤ 9)的几十种可能的构型 ,并应用量子化学从头算方法对它们的几何构型进行了优化 ,分析比较了这些构型的能量和稳定性。结果表明对于NixZry(x :y =1∶2 )... 详细信息

根据化学键理论和拓扑学原理 ,设计了非晶态团簇NixZry(x :y =1∶2或 2∶1,x +y≤ 9)的几十种可能的构型 ,并应用量子化学从头算方法对它们的几何构型进行了优化 ,分析比较了这些构型的能量和稳定性。结果表明对于NixZry(x :y =1∶2 )低对称性的平面构型最稳定 ,而NixZry(x :y =2∶1)三棱柱构型最稳定。这可能是由于两者外层价电子的数量差异所致 :Zr仅有 4个价电子 ,较适宜配位数低的平面构型 ,而Ni(4s2 3d8) ,更适宜立体构型。

关键词：团簇从头算量子化学镍锆非晶态合金形成过程构型

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Cu_(2)Se@C thin film with three-dimensional braided structure as a cathode material for enhanced Cu^(2+) storage

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Chinese Chemical Letters 2024年第5期35卷 523-528页

作者： Wenhao Chen Muxuan Wu Han Chen Lue mo yirong Zhu College of Materials and Advanced Manufacturing Hunan University of TechnologyZhuzhou 412007China Hunan Key of Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China

In the face of multiple challenges brought by the changes of global climate and environment,developing clean energy and updating green energy storage equipment are important ways to achieve carbon peak and carbon *** batteries have become a research hotspot due to their advantages of using the multivalent charge carrier,high ionic conductivity,environmental friendliness and cost *** this work,the Cu_(2)Se@C(Cu_(2)Se coated on carbon clothes)thin film with a three-dimensional braided structure is fabricated by a simple electrochemical deposition method for Cu^(2+)storage for the first *** with the commercial Cu_(2)Se powder,the well-designed Cu_(2)Se@C film shows enhanced specific capacity(640 mAh/g at 0.5 A/g)and rate performance(542 mAh/g at 5 A/g)as well as superior cycling stability(82.7%capacity retention after 1000 cycles at 1 A/g).The Cu^(2+)storage mechanism of the Cu_(2)Se@C electrode is based on a reversible phase transition process of Cu_(2)Se←→Cu_(2-x)Se←→CuSe←→CuSe_(2).In kinetic characteristic analysis,the Cu_(2)Se@C electrode demonstrates faster Cu^(2+)diffusion in discharge process than charge process resulting from the phase transition and the variation of interplanar *** work highlights a facile one-piece design strategy and opens a new gateway for the exploration of advanced aqueous energy storage systems.

关键词： Cu_(2)Se@C Cu^(2+)storage Conversion mechanism Kinetic characteristic Flexible energy storage

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Facile tuning of hydrogel properties by manipulating cationic-aromatic monomer sequences

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Science China Chemistry 2021年第9期64卷 1560-1568页

作者： Hailong Fan yirong Cai Jian Ping Gong Institute for Chemical Reaction Design and Discovery(WPI-ICReDD) Hokkaido UniversitySapporo001-0021Japan Graduate School of Life Science Hokkaido UniversitySapporo001-0021Japan Faculty of Advanced Life Science Hokkaido UniversitySapporo001-0021Japan Global Station for Soft Matter GI-CoRE Hokkaido UniversitySapporo001-0021Japan

Copolymer hydrogels formed from cationic and aromatic monomers with identical monomer compositions but different average sequences were synthesized by free-radical copolymerization in various *** found that hydrogels with one-componentrich segments are mechanically stronger than those with adjacent-rich monomer sequences in water,while hydrogels with a rich cation-πadjacent sequence showed excellent mechanical strength and underwater adhesion in saltwater(0.7 M Na Cl).The molecular mechanisms for these behaviors are discussed in terms of polymer *** work reveals the importance of monomeric sequences in determining hydrogel properties and provides a facile approach to develop hydrogels with different properties but the same monomer composition.

关键词： free-radical polymerization monomer sequence hydrogel cation-πinteractions underwater adhesion

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