Chinese Journal of Chemical Physics最新文献_第9页

Identifying diffusion limiting current to unravel the intrinsic kinetics of electrode reactions affected by mass transfer at rotating disk electrode 识别扩散限制电流以揭示旋转圆盘电极上受传质影响的电极反应的内在动力学

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-10-01 DOI: 10.1063/1674-0068/cjcp2006085

Mianle Xu, Wei Chen, Lingwen Liao, Zhen Wei, Jun Cai, Yanxin Chen

{"title":"Identifying diffusion limiting current to unravel the intrinsic kinetics of electrode reactions affected by mass transfer at rotating disk electrode","authors":"Mianle Xu, Wei Chen, Lingwen Liao, Zhen Wei, Jun Cai, Yanxin Chen","doi":"10.1063/1674-0068/cjcp2006085","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2006085","url":null,"abstract":"Rotating disk electrode systems are widely used to study the kinetics of electrocatalytic reactions that may suffer from insufficient mass transfer of the reactants. Kinetic current density at certain overpotential calculated by the Koutecky-Levich equation is commonly used as the metrics to evaluate the activity of electrocatalysts. However, it is frequently found that the diffusion limiting current density is not correctly identified in the literatures. Instead of kinetic current density, the measured current density normalized by diffusion limiting current density ( j/ jL) has also been frequently under circumstance where its validity is not justified. By taking oxygen reduction reaction/hydrogen oxidation reaction/hydrogen evolution reaction as examples, we demonstrate that identifying the actual diffusion limiting current density for the same reaction under otherwise identical conditions from the experimental data is essential to accurately deduce kinetic current density. Our analysis reveals that j/ jL is a rough activity metric which can only be used to qualitatively compare the activity trend under conditions that the mass transfer conditions and the roughness factor of the electrode are exactly the same. In addition, if one wants to use j/ jL to compare the intrinsic activity, the concentration overpotential should be eliminated.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44321720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Design of CuCs-doped Ag-based catalyst for ethylene epoxidation ccu掺杂银基乙烯环氧化催化剂的设计

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-08-01 DOI: 10.1063/1674-0068/cjcp2112246

Q. Wen, Haoxiang Xu, Yang Nan, Yuan Xie, D. Cheng

引用次数: 0

Alternative role of motif B in template dependent polymerase inhibition 基序B在模板依赖聚合酶抑制中的替代作用

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-06-01 DOI: 10.1063/1674-0068/cjcp2203053

Xueying Luo, Tiantian Xu, Xin Gao, Lu Zhang

{"title":"Alternative role of motif B in template dependent polymerase inhibition","authors":"Xueying Luo, Tiantian Xu, Xin Gao, Lu Zhang","doi":"10.1063/1674-0068/cjcp2203053","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2203053","url":null,"abstract":"Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) relies on the central molecular machine RNA-dependent RNA polymerase (RdRp) for the viral replication and transcription. Remdesivir at the template strand has been shown to effectively inhibit the RNA synthesis in SARS-CoV-2 RdRp by deactivating not only the complementary UTP incorporation but also the next nucleotide addition. How-ever, the underlying molecular mechanism of the second inhibitory point remains unclear. In this work, we have performed molecular dynamics simulations and demonstrated that such inhibition has not directly acted on the nucleotide addition at the active site. Instead, the translocation of Remdesivir from + 1 to − 1 site is hindered thermodynamically as the post-translocation state is less stable than the pre-translocation state due to the motif B residue G683. Moreover, another conserved residue S682 on motif B further hinders the dynamic translocation of Remdesivir due to the steric clash with the 1′-cyano substitution. Overall, our study has unveiled an alternative role of motif B in mediating the translocation when Remdesivir is present in the template strand and complemented our understanding about the inhibitory mechanisms exerted by Remdesivir on the RNA synthesis in SARS-CoV-2 RdRp.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45036427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Electron energy spectroscopic mapping of surface plasmon by parallel scanning method 平行扫描法表面等离子体电子能谱成像

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-06-01 DOI: 10.1063/1674-0068/cjcp2205090

Zhongfeng Li, Tuo Liu, Chunkai Xu, Xiangjun Chen

引用次数: 0

Comparative analysis of hydration layer reorientation dynamics of antifreeze protein and protein cytochrome P450 防冻蛋白和细胞色素P450蛋白水化层重取向动力学的比较分析

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-06-01 DOI: 10.1063/1674-0068/cjcp2203038

Hongfeng Yu, Qiang Zhang, W. Zhuang

{"title":"Comparative analysis of hydration layer reorientation dynamics of antifreeze protein and protein cytochrome P450","authors":"Hongfeng Yu, Qiang Zhang, W. Zhuang","doi":"10.1063/1674-0068/cjcp2203038","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2203038","url":null,"abstract":"Antifreeze proteins (AFPs) inhibit ice re-crystallization by a mechanism remaining largely elusive. Dynamics of AFPs’ hydration water and its involvement in the antifreeze activity have not been identified conclusively. We herein, by simulation and theory, examined the water reorientation dynamics in the first hydration layer of an AFP from the spruce budworm, Choristoneura fumiferana, compared with a protein cytochrome P450 (CYP). The increase of potential acceptor water molecules around donor water molecules leads to the acceleration of hydrogen bond exchange between water molecules. Therefore, the jump reorientation of water molecules around the AFP active region is accelerated. Due to the mutual coupling and excitation of hydrogen bond exchange, with the acceleration of hydrogen bond exchange, the rearrangement of the hydrogen bond network and the frame reorientation of water are accelerated. Therefore, the water reorientation dynamics of AFP is faster than that of CYP. The results of this study provide a new physical image of antifreeze protein and a new understanding of the antifreeze mechanism of antifreeze proteins.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43987517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Generalized fourth-order decompositions of imaginary time path integral: Implications of the harmonic oscillator 虚时间路径积分的广义四阶分解：谐振子的意义

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-06-01 DOI: 10.1063/1674-0068/cjcp2205089

Cong Wang, Lihan Zhang, Jian Liu, J. Shao

引用次数: 1

Excited-state double proton transfer of 1,8-dihydroxy-2-naphthaldehyde: A MS-CASPT2//CASSCF study 1,8-二羟基-2-萘醛激发态双质子转移:MS-CASPT2//CASSCF研究

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-06-01 DOI: 10.1063/1674-0068/cjcp2109163

Binbin Xie, Ke Wang, Pei-Ke Jia, Xiangxuan Liu, G. Cui

{"title":"Excited-state double proton transfer of 1,8-dihydroxy-2-naphthaldehyde: A MS-CASPT2//CASSCF study","authors":"Binbin Xie, Ke Wang, Pei-Ke Jia, Xiangxuan Liu, G. Cui","doi":"10.1063/1674-0068/cjcp2109163","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2109163","url":null,"abstract":"Excited-state double proton transfer (ESDPT) is a controversial issue which has long been plagued with theoretical and experimental communities. Herein, we took 1,8-dihydroxy-2-naphthaldehyde (DHNA) as a prototype and used combined complete active space self-consistent field (CASSCF) and multi-state complete active-space second-order perturbation (MS-CASPT2) methods to investigate ES-DPT and excited-state deactivation pathways of DHNA. Three different tautomer minima of S1-ENOL, S1-KETO-1, and S1-KETO-2 and two crucial conical intersections of S1S0-KETO-1 and S1S0-KETO-2 in.and between the S0 and S1 states were obtained. S1-KETO-1 and S1-KETO-2 should take responsibility for experimentally observing dual-emission bands. In addition, two-dimensional potential energy surfaces (2D-PESs) and linear interpolated internal coordinate paths connecting relevant structures were calculated at the MS-CASPT2//CASSCF level and confirmed a stepwise ESDPT mechanism. Specifically, the first proton transfer from S1-ENOL to S1-KETO-1 is barrierless, whereas the second one from S1-KETO-1 to S1-KETO-2 demands a barrier of ca. 6.0 kcal/mol. The linear interpolated internal coordinate path connecting S1-KETO-1 (S1-KETO-2) and S1S0-KETO-1 (S1S0-KETO-2) is uphill with a barrier of ca. 12.0 kcal/mol, which will trap DHNA in the S1 state while therefore enabling dual-emission bands. On the other hand, the S1/S0 conical intersections would also prompt the S1 system to decay to the S0 state, which could be to certain extent suppressed by locking the rotation of the C5−C8−C9−O10 dihedral angle. These mechanistic insights are not only helpful for understanding ESDPT but also useful for designing novel molecular materials with excellent photoluminescent performances.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58525722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Boron-containing thermally activated delayed blue fluorescence materials via donor tuning: A theoretical study 通过供体调谐热激活含硼延迟蓝色荧光材料的理论研究

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-06-01 DOI: 10.1063/1674-0068/cjcp2203039

Yanfang Ji, Quansong Li

{"title":"Boron-containing thermally activated delayed blue fluorescence materials via donor tuning: A theoretical study","authors":"Yanfang Ji, Quansong Li","doi":"10.1063/1674-0068/cjcp2203039","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2203039","url":null,"abstract":"Based on the boron-containing thermally activated delayed fluorescence (TADF) compound p-AC (AC: acridine) 5,9-dioxa-13b-boranaphtho [3,2,1-de] anthracene (a), a series of new TADF molecules b1−b4 were designed via adding two nitrogen atoms at the AC donor part. Density functional theory and time-dependent density functional theory calculations were performed on the frontier orbital energy levels, emission spectra, singlet-triplet states energy gaps (Δ EST), reverse intersystem crossing (RISC) rate constant ( kRISC) for compounds a and b1−b4. Our calculation results show that the maximum emission wavelengths of b1−b4 are significantly blue-shifted by 47−125 nm compared with that of a. Molecules b1 and b3 exhibit dark-blue emission, while molecules b2 and b4 display light-blue emission, indicating that these four derivatives could be potential organic light-emitting diode (OLED) candidates with blue-light emitting. Moreover, we found the RISC processes in a, b2, and b4 can occur not only from T1 state to S1 state, but also from T2 state to S1 state significantly, while the RISC processes in b1 and b3 mainly take place via the T2→S1 hot exciton way. Importantly, the T1→S1 kRISC values of b2 and b4 are predicted to be two to three times of that of a, indicating enhanced TADF property. Our results not only provide two promising boron-based TADF candidates (b2 and b4), but also offer useful theoretical basis for the design of blue OLED materials.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47838231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A mechanistic switch in C−H bond activation by elusive FeV(O)(TAML) reaction intermediate: A theoretical study 难以捉摸的FeV（O）（TAML）反应中间体激活C−H键的机制转换：理论研究

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-04-01 DOI: 10.1063/1674-0068/cjcp2111230

A. Zhou, Zhiqiang Fu, X.-M. Cao, Yufen Zhao, Yong Wang

引用次数: 0

Regulation of excited-state intramolecular proton transfer process and photophysical properties for benzoxazole isothiocyanate fluorescent dyes by changing atomic electronegativity 改变原子电负性对苯并恶唑异硫氰酸酯荧光染料激发态质子转移过程和光物理性质的调控

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-04-01 DOI: 10.1063/1674-0068/cjcp2110209

Hongling Zhang, Qingtong Liu, Yiying Wang, Zhe Tang, P. Zhou

{"title":"Regulation of excited-state intramolecular proton transfer process and photophysical properties for benzoxazole isothiocyanate fluorescent dyes by changing atomic electronegativity","authors":"Hongling Zhang, Qingtong Liu, Yiying Wang, Zhe Tang, P. Zhou","doi":"10.1063/1674-0068/cjcp2110209","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2110209","url":null,"abstract":"Excited-state intramolecular proton transfer (ESIPT) is favored by researchers because of its unique optical properties. However, there are relatively few systematic studies on the effects of changing the electronegativity of atoms on the ESIPT process and photophysical properties. Therefore, we selected a series of benzoxazole isothiocyanate fluorescent dyes (2-HOB, 2-HSB, and 2-HSeB) by theoretical methods, and systematically studied the ESIPT process and photophysical properties by changing the electronegativity of chalcogen atoms. The calculated bond angle, bond length, energy gap, and infrared spectrum analysis show that the order of the strength of intramolecular hydrogen bonding of the three molecules is 2-HOB<2-HSB<2-HSeB. Correspondingly, the magnitude of the energy barrier of the potential energy curve is 2-HOB>2-HSB>2-HSeB. In addition, the calculated electronic spectrum shows that as the atomic electronegativity decreases, the emission spectrum has a redshift. Therefore, this work will offer certain theoretical guidance for the synthesis and application of new dyes based on ESIPT properties.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49179283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0