Chinese Journal of Chemical Physics最新文献_第10页

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":" ","pages":""},"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

High resolution laser excitation spectra and Franck-Condon factors of A2Π−X2Σ+ electronic transition of MgF MgF的高分辨激光激发光谱和A2π−X2∑+电子跃迁的Franck-Condon因子

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-02-01 DOI: 10.1063/1674-0068/cjcp2109151

J. Gu, Zengjun Xiao, Chunting Yu, Qiang Zhang, Yang Chen, Dongfeng Zhao

{"title":"High resolution laser excitation spectra and Franck-Condon factors of A2Π−X2Σ+ electronic transition of MgF","authors":"J. Gu, Zengjun Xiao, Chunting Yu, Qiang Zhang, Yang Chen, Dongfeng Zhao","doi":"10.1063/1674-0068/cjcp2109151","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2109151","url":null,"abstract":"Magnesium monofluoride (MgF) is proposed as an ideal candidate radical for direct laser cooling. Here, the rotationally resolved laser spectra of MgF for the A2Π− X2Σ+ electronic transition system were recorded by using laser induced fluorescence technique. The MgF radicals were produced by discharging SF6/Ar gas mixtures between the tips of two magnesium needles in a supersonic jet expansion. We recorded a total of 19 vibrational bands belonging to three sequences of Δ v=0, ±1 in the region of 348-370 nm. Accurate spectroscopic constants for both X2Σ+ and A2Π states are determined from rotational analysis of the experimental spectra. Spectroscopic parameters, including the Franck-Condon factors (FCFs), are determined from the experimental results and the Rydberg-Klein-Rees (RKR) calculations. Significant discrepancies between the experimentally measured and RKR-calculated FCFs are found, indicating that the FCFs are nearly independent of the spin-orbit coupling in the A2Π state. Potential energy curves (PECs) and FCFs determined here provide necessary data for the theoretical simulation of the laser-cooling scheme of MgF.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48499846","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: 5

15 N/14N isotopic exchange in the dissociative adsorption of N2 on tantalum nitride cluster anions Ta3N3− 氮化钽簇阴离子Ta3N3−上15n /14N的同位素交换

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-02-01 DOI: 10.1063/1674-0068/cjcp2112286

Zi-Yu Li, Li-Hui Mou, G. Jiang, Qing-Yu Liu, Sheng‐Gui He

{"title":"15 N/14N isotopic exchange in the dissociative adsorption of N2 on tantalum nitride cluster anions Ta3N3−","authors":"Zi-Yu Li, Li-Hui Mou, G. Jiang, Qing-Yu Liu, Sheng‐Gui He","doi":"10.1063/1674-0068/cjcp2112286","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2112286","url":null,"abstract":"Adsorption and activation of dinitrogen (N2) is an indispensable process in nitrogen fixation. Metal nitride species continue to attract attention as a promising catalyst for ammonia synthesis. However, the detailed mechanisms at a molecular level between reactive nitride species and N2 remain unclear at elevated temperature, which is important to understand the temperature effect and narrow the gap between the gas phase system and condensed phase system. Herein, the 14N/15N isotopic exchange in the reaction between tantalum nitride cluster anions Ta314N3− and 15N2 leading to the regeneration of 14N2/14N15N was observed at elevated temperature (393−593 K) using mass spectrometry. With the aid of theoretical calculations, the exchange mechanism and the effect of temperature to promote the dissociation of N2 on Ta3N3− were elucidated. A comparison experiment for Ta314N4−/15N2 couple indicated that only desorption of 15N2 from Ta314N415N2− took place at elevated temperature. The different exchange behavior can be well understood by the fact that nitrogen vacancy is a requisite for the dinitrogen activation over metal nitride species. This study may shed light on understanding the role of nitrogen vacancy in nitride species for ammonia synthesis and provide clues in designing effective catalysts for nitrogen fixation.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41360401","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

Probing effect of solvation on photoexcited quadrupolar donor-acceptor-donor molecule via ultrafast Raman spectroscopy 用超快拉曼光谱探测溶剂化对光激发四极供体-受体-供体分子的影响

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-02-01 DOI: 10.1063/1674-0068/cjcp2111223

Wei Zhang, J. Kong, Wenqi Xu, Xinmiao Niu, D. Song, Weimin Liu, A. Xia

{"title":"Probing effect of solvation on photoexcited quadrupolar donor-acceptor-donor molecule via ultrafast Raman spectroscopy","authors":"Wei Zhang, J. Kong, Wenqi Xu, Xinmiao Niu, D. Song, Weimin Liu, A. Xia","doi":"10.1063/1674-0068/cjcp2111223","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2111223","url":null,"abstract":"The symmetric and quadrupolar donor-acceptor-donor (D-A-D) molecules usually exhibit excited-state charge redistribution process from delocalized intramolecular charge transfer (ICT) state to localized ICT state. Direct observation of such charge redistribution process in real-time has been intensively studied via various ultrafast time-resolved spectroscopies. Femtosecond stimulated Raman spectroscopy (FSRS) is one of the powerful methods which can be used to determine the excited state dynamics by tracking vibrational mode evolution of the specific chemical bonds within molecules. Herein, a molecule, 4,4′-(buta-1,3-diyne-1,4-diyl)bis( N, N-bis(4-methoxyphenyl)aniline), that consists of two central adjacent alkyne (-C≡C-) groups as electron-acceptors and two separated, symmetric N, N-bis(4-methoxyphenyl)aniline at both branches as electron-donors, is chosen to investigate the excited-state photophysical properties. It is shown that the solvation induced excited-state charge redistribution in polar solvents can be probed by using femtosecond stimulated Raman spectroscopy. The results provide a fundamental understanding of photoexcitation induced charge delocalization/localization properties of the symmetric quadrupolar molecules with adjacent vibrational markers located at central position.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47511963","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

Solvent effects on excited-state relaxation dynamics of paddle-wheel BODIPY-Hexaoxatriphenylene conjugates: Insights from non-adiabatic dynamics simulations 溶剂对桨轮BODIPY-六氧杂三苯基偶联物激发态弛豫动力学的影响：非绝热动力学模拟的启示

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-02-01 DOI: 10.1063/1674-0068/cjcp2110214

Wen-Kai Chen, G. Cui, Xiangxuan Liu

{"title":"Solvent effects on excited-state relaxation dynamics of paddle-wheel BODIPY-Hexaoxatriphenylene conjugates: Insights from non-adiabatic dynamics simulations","authors":"Wen-Kai Chen, G. Cui, Xiangxuan Liu","doi":"10.1063/1674-0068/cjcp2110214","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2110214","url":null,"abstract":"Understanding the excited state dynamics of donor-acceptor (D-A) complexes is of fundamental importance both experimentally and theoretically. Herein, we have first explored the photoinduced dynamics of a recently synthesized paddle-wheel BODIPY-hexaoxatriphenylene (BODIPY is the abbreviation for BF2-chelated dipyrromethenes) conjugates D-A complexes with the combination of both electronic structure calculations and non-adiabatic dynamics simulations. On the basis of computational results, we concluded that the BODIPY-hexaoxatriphenylene (BH) conjugates will be promoted to the local excited (LE) states of the BODIPY fragments upon excitation, which is followed by the ultrafast exciton transfer from LE state to charge transfer (CT). Instead of the photoinduced electron transfer process proposed in previous experimental work, such a exciton transfer process is accompanied with the photoinduced hole transfer from BODIPY to hexaoxatriphenylene. Additionally, solvent effects are found to play an important role in the photoinduced dynamics. Specifically, the hole transfer dynamics is accelerated by the acetonitrile solvent, which can be ascribed to significant influences of the solvents on the charge transfer states, i.e. the energy gaps between LE and CT excitons are reduced greatly and the non-adiabatic couplings are increased in the meantime. Our present work not only provides valuable insights into the underlying photoinduced mechanism of BH, but also can be helpful for the future design of novel donor-acceptor conjugates with better optoelectronic performance.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43863700","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

QM/MM study on enzymatic mechanism in sinigrin biosynthesis 缬氨酸生物合成酶机制的QM/MM研究

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-02-01 DOI: 10.1063/1674-0068/cjcp2111250

Yafang Guo, Yajun Liu

{"title":"QM/MM study on enzymatic mechanism in sinigrin biosynthesis","authors":"Yafang Guo, Yajun Liu","doi":"10.1063/1674-0068/cjcp2111250","DOIUrl":"https://doi.org/10.1063/1674-0068/cjcp2111250","url":null,"abstract":"As the major and abundant type of glucosinolates (GL) in plants, sinigrin has potential functions in promoting health and insect defense. The final step in the biosynthesis of sinigrin core structure is highly representative in GL compounds, which corresponds to the process from 3-methylthiopropyl ds-GL to 3-methylthiopropyl GL catalyzed by sulfotransferase (SOT). However, due to the lack of the crystallographic structure of SOT complexed with the 3-methylthiopropyl GL, little is known about this sulfonation process. Fortunately, the crystal structure of SOT 18 from Arabidopsis thaliana (AtSOT18) containing the substance (sinigrin) similar to 3-methylthiopropyl GL has been determined. To understand the enzymatic mechanism, we employed molecular dynamics (MD) simulation and quantum mechanics combined with molecular mechanics (QM/MM) methods to study the conversion from ds-sinigrin to sinigrin catalyzed by AtSOT18. The calculated results demonstrate that the reaction occurs through a concerted dissociative mechanism. Moreover, Lys93, Thr96, Thr97, Tyr130, His155, and two enzyme peptide chains (Pro92-Lys93 and Gln95-Thr96-Thr97) play a role in positioning the substrates and promoting the catalytic reaction by stabilizing the transition state geometry. Particularly, His155 acts as a catalytic base while Lys93 acts as a catalytic acid in the reaction process. The presently proposed concerted dissociative mechanism explains the role of AtSOT18 in sinigrin biosynthesis, and could be instructive for the study of GL biosynthesis catalyzed by other SOTs.","PeriodicalId":10036,"journal":{"name":"Chinese Journal of Chemical Physics","volume":" ","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47357641","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

Basis sets dependency in constructing spectroscopy-accuracy Ab Initio global electric dipole moment functions 在构造光谱精度从头算全局电偶极矩函数中的基集依赖性

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-02-01 DOI: 10.1063/1674-0068/cjcp2111244

Yu Zhai, Hui Li

引用次数: 0

Ultrafast Decay Dynamics of 2-Hydroxypyridine Excited to the S1 Electronic State 激发至S1电子态的2-羟基吡啶的超快衰变动力学

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-01-01 DOI: 10.1063/1674-0068/cjcp2111255

引用次数: 2

Ab initio Nonadiabatic Dynamics of Semiconductor Nanomaterials via Surface Hopping Method 基于表面跳变法的半导体纳米材料从头计算非绝热动力学

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-01-01 DOI: 10.1063/1674-0068/cjcp2111247

引用次数: 0

The low-lying isomers of (TiO2)n (n=2-8) clusters (TiO2)n (n=2-8)簇的低洼异构体

IF 1 4区化学

Chinese Journal of Chemical Physics Pub Date : 2022-01-01 DOI: 10.1063/1674-0068/cjcp2111245

引用次数: 1