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Laboratory of Molecular Reaction Stereodynamics

Group

Our group is affilated with Department of Chemical Physics, University of Science and Technology of China at Hefei, as well as Hefei National Laboratory for Physical Sciences at Microscale. Now we are investigating the electron-induced/driven chemical reactions in gas- and lqiuid-phases. Our group continuously has limited openings for graduate students /postdoctoral associates. Skills in atom, molecule, ion, or electron impact experiments / theories are particularly valuable.

Current Members

Prof. Shan Xi Tian (PI, sxtian@ustc.edu.cn)

  • Dr. Jie Hu (PD, huadie08@mail.ustc.edu.cn)
  • Dr. Bin Wu (PD, wubin@ustc.edu.cn)
  • Dr. Xiao-Fei Gao (PD, gaoxf12@mail.ustc.edu.cn)
  • Zi-Wei CHEN (D3, czw14@mail.ustc.edu.cn)
  • Zi-Yuan LI (D2,liziyuan@mail.ustc.edu.cn)
  • Jing-Chen XIE(D1,xjc1997@mail.ustc.edu.cn)
  • Yaya ZHI (M2,zyy1997@mail.ustc.edu.cn)
  • Meng-Yuan FAN (M2,fanmy@mail.ustc.edu.cn)
  • Zixin CHEN (M2,chenzx17@mail.ustc.edu.cn)
  • Qiang GUO (M1,guoq20@mail.ustc.edu.cn)
  • Tiantian TONG (M1,tongtt@mail.ustc.edu.cn)
  • Caixiu ZHANG (M2, joint member)
  • Raziq NAWAZ (D4, raziqnawaz1@gmail.com; suspended)
  • Recent Alumni (Since 2010)

  • 2020: Xiao-Fei Gao (PhD); Chun-Xiao Wu (PhD); Xin Meng (MS); Miao-Miao He (MS)
  • 2019: Hao Li (PhD)
  • 2018: Xu-Dong Wang (PhD, Top-level CAS president awardee); Jie Hu (PhD); Ling-Ling Chen (MS); Jin-Chen Xie (BS)
  • 2017: Yu-Feng Ye (MS); Zi-Yuan Li(BS)
  • 2016: Wen-Ling Feng (PhD); Meng-Yang Li (MS)
  • 2015: Chuan-Jin Xuan (MS)
  • 2014: Cen-Feng Fu (PhD); Tao Jin (BS); Qi Yu (BS); Xuejun Gong (BS)
  • 2013: Lei Xia (PhD, CAS president awardee), Zhou Zhang (MS), Xian-Jin Zeng (MS), Hong-Kai Li (MS), Meng-Yang Li (BS), Yifan Liu (BS)
  • 2012: Bin Wu (PhD); Yong-Feng Wang (PhD); Yun-Feng Xu (PhD); Fan Zhang (BS); Wen-Hao Liu (BS)
  • 2011: Liuli Chen (PhD); Sheng-Xi Jin (BS); Yu-Feng Ye (BS)
  • 2010: Hai-Bei Li (PhD); Qiang Feng (MS); Xiang-Ling Meng (BS); Jia-Xing Lin (BS), Xian-Jin Zeng (BS), Fan Zheng (BS)
  • Recent News

    March 2021

    Ion-Molecule Reaction

    Zhi, Y.; et al., J. Phys. Chem. A

    In contrast to photoionization, the parent cationic yields C2H2Cl2+ in the high-lying electronic states are found in the chrage exchange reactions between Ar+ and trans-/cis-dichloroethylene. Differences between the charge transfer in ion-molecule reaction and photoionization are elucidated in this work. The manuscript is accepted for publication and selected as Cover story on JPCA.

    January 2021

    Superexcited-State CN¯

    Gao, X.-F.; et al., Commun. Chem.

    In the dissociative electron attachment to BrCN, the CN¯ yields are found in the superexcited vibrational states or the superexcited electronic states and have the lifetime longer than 5 microseconds. This finding sheds new lights on its abundance and the origins of some compounds in interstellar space. This paper is now accepted for publication on Commnuciations Chemistry.

    Research

    Basic features of chemical reaction are inter-/intra-molecular energy and charge redistributions and molecular reconstructions. Electron- or charge-transfer process is a doorway of chemical reactions in plasma, flame, interstellar space, and solutions. Besides the developments of some unique and state-of-the-art experimental techniques, we are interested in the following three topics about electron-driven chemical reactions in gas- and liquid-phases.

    Dissociative Electron Attachment

    since 2012

    Dissociative electron attachment (DEA), e- + AB -> A + B-, is an important process in the irradiation damages to biological systems, of the substance evolutions in the interstellar space and planets' upper atmospheres. On the fundamental view, DEA is a key step of electron-induced or -driven chemical reactions.To have insights into its dynamics, our experimental apparatus (Rev. Sci. Instrum. 2012, 83, 013108) is now developed by combinational usage of the time-sliced anion velocity map imaging (VMI) and a trochoidal electron monochromator.

    We further supplement a spectrometer to record the electron-impact photoemissions (see J. Chem. Phys. 2020, 153, 024301 and the following pciture), and the laser-induced fluorescence (LIF), resonance-enhanced multiphoton ionization (REMPI) and the pump-probe techiques will be introduced into this apparatus.

    Ion-Molecule Reaction

    since 2017

    As a secondary reaction in the electron-induced or -driven chemical reactions, ion-molecule reaction is another important process. Recently, we set up a VMI apparatus to investigate the cation/anion-molecule reaction dynamics, in which our unique ion source is employed to produce the well-confined pulsed ion bunches. Now the delay-line-detector (DLD) is introduced, which enables us to record the three-dimensional Newton sphere of the product ions. This experimental improvement greatly facilitates the stereodynamics studies of charge- and energy-transfer.

    Neutral polar molecule receives a force in electric field, due to Stark effect. This phenomenon leads to an application about manipulation of a molecule with large dipole moment in an inhomogeneous electrostatic field. A double-electrode device (the golden part in the following picture) is designed and will be used for the studies of the electron-/ion-impact reactions with the rotational-state or conformational selected molecule.

    Liquid & Surface

    since 2018

    To study the electron-induced reactions in liquid and its interface (consisting of the outermost layer and subsurface), we established time-delayed (resolved) mass spectrometry as a conceptually new method.

    Now a tandem mass spectrometer is developed on the basis of above apparatus, by supplementing a quadrupole mass filter to identify individual ionic species. Owing to this development, the molecular orientation both in the outermost layer and the subsurface can be determined, more importantly, in situ existence of the molecular clusters in the subsurface is confirmed for the first time. This powerful technique is applicable for investigation on the chemical reactions in different localtions of the liquid-vapor interface.

    Besides the electron-induced reactions, we also investigate the ion-liquid surface reactions by using a pulsed ion beam. An infrared picosend-pulsed laser will be introduced into this apparatus, which enables us to do pump-probe experiments of the electron-induced reactions at the liquid surface.

    Time-Resolved Transmission Electron Microscopy

    since 2020

    This new project includes the development of ultrafast and coherent electron pulsed (picoseconds to femtoseconds) beam based upon a transmission electron microscope (TEM) and applications for the dynamics studies of structural (phase) transitions and chemical reactions in condensed (liquid) phase.

    Publication (since 2010)

    Hu, J.; Xie, J.-C.; Wu, C.-X.; Tian, S. X.* Superposition-state N2+ produced in the intermolecular charge transfer from Ar+ to N2. (Submitted)

    Zhi, Y.; Hu, J.; Xie, J.-C.; Tian, S. X.* Ion-molecule charge exchange reactions between Ar+ and trans-/cis-dichloroethylene. Journal of Physical Chemistry A, 2021, 125: 2573-2580. (a contribution article of Cheuk-Yiu Ng Festschrift Virtual Special Issue, Suppl. Cover)

    Hu, J.; Wu, C.-X.; Zhi, Y.; Xie, J.-C.; He, M.-M.; Tian, S. X.* Stereodynamics observed in the reactive collisions of low-energy Ar+ with randomly oriented O2. Journal of Physical Chemistry Letters 2021, 12: 1346-1351.

    Li, Z.; Chen, Z.; Hu, J.; Li, H.; Tian, S. X.* A new experimental method for investigations on the microstructure of liquid-vapor interface. Chinese Journal of Chemical Physics. 2021, 34: 43-50. (An invited review of the special issue on New Advanced Experimental Techniques on Chemical Physics).

    Gao, X. -F.; Xie, J.-C.; Li, H.; Meng, X.; Wu, Y.; Tian, S. X.* Direct observation of long-lived cyanide anions in superexcited states. Communications Chemistry. 2021, 4: 13. (open access, https://www.nature.com/articles/s42004-021-00450-0)

    Gao, X. -F.†; An, F.†; Li, H.; Xie, J.-C.; Wang, X.-D.; Meng, X.; Wu, B.; Xie, D.-Q.*; Tian, S. X.* Probing the potential energy surfaces of BrCN¯ by dissociative electron attachment. Journal of Physical Chemistry Letters 2020, 11: 9110-9116. (†contributed equally)

    Wu, B; Wang, X.-D.; Gao, X.-F.; Li, H.; Tian, S. X.* Dissociative electron attachment to carbon dioxide. Chinese Journal of Chemical Physics. 2020, 33: 521-531. (An invited review of the special issue on the Chinese Chemical Society's 16th National Chemical Dynamics Symposium; Cover story).

    Chen, Z.; Fu, C.-F.; Li, Z.; Hu, J.; Li, H.; Yang, J.; Tian, S. X.* Identifying the molecular orientation and clusters in the liquid-vapor interface of 1-propanol by time-delayed mass spectrometry. Journal of Physical Chemistry Letters 2020, 11: 7510-7516.

    Meng, X.; Wu, B.; Gao, X.-F.; Xie, J.-C.; Li, H.; Yu, Y.; Zhao, D.; Tian, S. X.* Vibrationally-resolved photoemissions of N2 (3Πu →a3Πg) and CO (b3Σ+ →a3Π) by low-energy electron impacts. Journal of Chemical Physics 2020, 153: 024301.

    Wang, X.-D.; Gao, X.-F.; Li, H.; Wu, B.; Tian, S. X.* Dissociative electron attachment to polyatomic molecules. Journal of Physics: Conference Series 2020, 1412: 052010.

    He, M.-M.; Hu, J.; Wu, C.-X.; Zhi, Y.; Tian, S. X.* Collison-energy dependence of the ion-molecule charge exchange reaction Ar+ + CO -> Ar + CO+. Journal of Physical Chemistry A 2020, 124: 3358-3363.

    Wu, C.-X.; Hu, J.; He, M.-M.; Zhi, Y.; Tian, S. X.* Ion momentum imaging study of the ion-molecule reaction Ar+ + O2 -> Ar + O2+. Physical Chemistry Chemical Physics 2020, 22: 4640-4646.

    Gao, X.-F.; Li, H.; Meng, X.; Xie, J.-C.; Tian, S. X.* Synchronous and asynchronous dynamics of the concerted three-body dissociations of temporary negative ion CH2F2-. Journal of Chemical Physics 2020, 152: 084305 (Selected as Editor's Pick).

    Li, H.; Gao, X.-F.; Meng, X.; Tian, S. X.* Dissociative electron attachment to molecular acetonitrile. Journal of Physical Chemistry A 2019, 123: 9089-9095 (cover story).

    Wu, C.-X.; Hu, J.; He, M.-M.; Tian, S. X.* Ion momentum imaging study of the ion-molecule charge exchange reaction of Ar+ + CO2. Journal of Physical Chemistry A 2019, 123: 8536-8541 (cover story).

    Li, H.; Gao, X.-F.; Meng, X.; Tian, S. X.* Dissociative electron attachment to vibrationally excited CO2. Physical Review A 2019, 99: 032703.

    Gao, X.-F.; Li, H.; Meng, X.; Tian, S. X.* Ion-pair dissociations of BrCN by electron impacts. Chinese Journal of Chemical Physics 2019, 32: 89-92. (Dedicated to Professor Kopin Liu on the occasion of his 70th birthday)

    Hu, J.; Wu, C.-X.; Ma, Y.-S.; Tian, S. X.* Collision-energy dependence of the ion-molecule charge exchange reaction Ar+ + NO. Journal of Physical Chemistry A 2018, 122: 9171-9176 (cover story).

    Chen, L.; Chen, Z.; Li, Z.; Hu, J.; Tian, S. X.* Time-delayed mass spectrometry of the low-energy electron impact with a liquid beam surface. Review of Scientific Instruments 2018, 89: 103102.

    Hu, J.; Wu, C.-X.; Tian, S. X.* Note: A well-confined pulsed low-energy ion beam: Test experiments of Ar+. Review of Scientific Instruments 2018, 89: 066104.

    Wang, Y.-F.*; Tian, S. X. Low-energy electron attachment to serine conformers: Shape resonances and dissociation dynamics. Chinese Journal of Chemical Physics 2017, 30: 173-185.

    Ye, Y-.F.; Fu, C-.F.; Tian, S. X.* A molecular dynamics simulation study of ClF in water: Halogen bonding interaction in liquid. Chinese Journal of Chemical Physics 2017, 30: 25-28.

    Li, M.-Y.; Gao, X.-F.; Wang, X.-D.; Li, H.; Tian, S. X.* S- velocity images of dissociative electron attachment to OCS. International Journal of Mass Spectrometry 2016, 404: 20-23 (cover story).

    Feng, W.-L.; Tian, S. X.* Ab initio molecular dynamics simulation study of dissociative electron attachment to C6H5(CH2)nCl (n = 0, 1, 2, 3, 4). International Journal of Mass Spectrometry 2016, 399-400: 40-43.

    Wang, X.-D.; Gao, X.-F.; Xuan, C.-J., Tian, S. X.* Dissociative electron attachment to CO2 produces molecular oxygen. Nature Chemistry 2016, 8: 258-263.

    Tian, S. X.*; Luo, Y. Reply to "Comment on 'Coherent interference in the resonant dissociative electron attachment to carbon monoxide'". Physical Review A 2015, 91: 056702.

    Wang, X.-D.; Xuan, C.-J.; Luo, Y.; Tian, S. X.* Coherent resonances observed in the dissociative electron attachment to carbon monoxide. Journal of Chemical Physics 2015, 143: 066101.

    Feng, W.-L.; Tian, S. X.* Ab initio molecular dynamics simulation study of dissociative electron attachment to dialanine conformers. Journal of Physical Chemistry A 2015, 119: 1838-1845.

    Wang, X.-D.; Xuan, C.-J.; Feng, W.-L.; Tian, S. X.* Dissociative electron attachments to ethanol and acetaldehyde: A combined experimental and simulation study. Journal of Chemical Physics 2015, 142: 064316.

    Xuan, C.-J.; Wang, X.-D.; Xia, L.; Wu, B.; Li, H.; Tian, S. X.* Dissociative electron attachment to 1,2-dichlorobenzene by using mass spectrometry with phosphor screen. Chinese Journal of Chemical Physics 2014, 27: 628-630.

    Fu, C.-F.; Tian, S. X.* Different aggregation dynamics of the benzene-water mixtures. Physical Chemistry and Chemical Physics 2014, 16: 21957-21963 (backcover story).

    Xia, L.; Wang, X.-D.; Xuan, C.-J.; Zeng, X.-J.; Li, H.-K.; Tian, S. X.*; Pan, Y.; Lau, K.-C.* State mixing by spin-orbit coupling of the anionic chloroiodine dissociations. Journal of Chemical Physics (Communication) 2014, 140: 041106.

    Yan, S.; Zhang, P.; Ma, X.*; Xu, S.; Tian, S. X.; Li, B.; Zhu, X. L.; Feng, W. T.; Zhao, D. M. Dissociation of the Ar trimer induced by a third atom in high-energy electron-impact ionization. Physical Review A 2014, 89: 062707.

    Tian, S. X.*; Wu, B.; Xia, L.; Li, H.-K.; Zeng, X.-J.; Luo, Y.; Yang, J. L. Coherent interference in the resonant dissociative electron attachment to carbon monoxide. Physical Review A 2013, 88: 012708.

    Fu, C.-F.; Tian, S. X.* Thermodynamics of ammonia and ammonium ion at the aqueous solution-air interfaces. Journal of Physical Chemistry C 2013, 117: 13011-13020.

    Li, H.-K.; Xia, L.; Zeng, X.-J.; Tian, S. X.* Two- and three-body dissociation dynamics of temporary negative ion NF3-. Journal of Physical Chemistry A 2013, 117: 3176-3182.

    Chu, G.B.; Chen, J; Liu, F.Y.*; Shan, X.B.; Sheng, L.S.; Xu, Y.F.; Tian, S. X. Positive and negative photoion spectroscopy study of C2Cl4. Molecular Physics 2013, 111: 427-435.

    Zeng, X.-J.; Xia, L.; Li, H.-K.; Lau, K.-C.; Tian, S. X.* Anion velocity imaging study of the dissociative electron attachment to CFCl3. Physical Review A 2013, 87: 012711. Selected into 'Kaleidoscope' of PRA Journal web site (January, 2013).

    Xia, L.; Zeng, X.-J.; Li, H.-K.; Wu, B.; Tian, S. X.* Orientation effect in the low-energy electron attachment to the apolar carbon tetrafluoride molecule. Angewandte Chemie, International Edition (Communication) 2013, 52: 1013-1016.

    Xia, L.; Wu, B.; Li, H.-K.; Zeng, X.-J.; Tian, S. X.* Imaging the indirect dissociation dynamics of temporary negative ion: N2O- -> N2 + O-. Journal of Chemical Physics (Communication) 2012, 137: 151102 (4 pages). One of the journal's Top 20 most read articles, in Oct. 2012.

    Wu, B.; Xia, L.; Wang, Y.-F.; Li, H.-K.; Zeng, X.-J.; Tian, S. X.* Renner-Teller effect on dissociative electron attachments to carbon dioxide. Physical Review A 2012, 85: 052709.

    Tian, S. X. Photoion-pair dissociation dynamics of polyatomic molecules with synchrotron radiation. Physical Chemistry Chemical Physics 2012, 14: 6433-6443 (Perspective Article).

    Wang, Y.-F.; Tian, S. X.* Low-energy electron collisions with formamide using the R-matrix method. Physical Review A 2012, 85: 012706.

    Wu, B.; Xia, L.; Li, H.-K.; Zeng, X.-J.; Tian, S. X.* Positive / negative ion velocity mapping apparatus for electron-molecule reactions. Review of Scientific Instruments 2012, 83: 013108.

    Xu, Y.-F.; Tian, S. X.*; Chen, L.-L.; Liu, F.-Y.; Sheng, L. S. Positive and negative photoion mass spectroscopy study of monochlorothiophenes. Journal of Physical Chemistry A 2011, 115: 11920-11929.

    Wang, Y.-F.; Tian, S. X.* Low-energy electron impact with thioformaldehyde. Physical Review A 2011, 84: 022709.

    Wang, Y.-F.; Tian, S. X.*; Yang, J. L. Resonant dissociative electron attachments to cysteine and cystine. Physical Chemistry Chemical Physics 2011, 13: 15597-15602.

    Fu, C.-F.; Tian, S. X.* A comparative study for molecular dynamics simulations of liquid benzene. Journal of Chemical Theory and Computation 2011, 7: 2240-2252. One of the journal's Top 20 most downloaded articles, July, 2011.

    Chen, L.-L.; Tian, S. X.*; Xu, Y.-F.; Chu, G.-B.; Liu, F.-Y.; Shan, X.-B.; Sheng, L. S. Vacuum ultraviolet negative photoion spectroscopy of dichlorodifluoromethane. International Journal of Mass Spectrometry 2011, 305: 20-25.

    Chen, L.-L.; Tian, S. X.*; Xu, Y.-F.; Chu, G.-B.; Liu, F.-Y.; Shan, X.-B.; Sheng, L. S. Ion-pair photodissociation study of trichloromonofluoromethane. Chinese Journal of Chemical Physics 2011, 24: 261-266.

    Chen, L.-L.; Xu, Y.-F.; Feng, Q.; Tian, S. X.*; Liu, F.-Y.; Shan, X.-B.; Sheng, L. S. Vacuum ultraviolet negative photoion spectroscopy of chloroform. Journal of Physical Chemistry A 2011, 115: 4248-4254.

    Wang, Y.-F.; Tian, S. X.* Shape-resonance states of the low-energy electron attachments to DNA base tautomers. Physical Chemistry Chemical Physics 2011, 13: 6169-6175.

    Tian, S. X.*; Xu, Y.-F.; Wang, Y.-F.; Feng, Q.; Chen, L.-L.; Sun, J. D.; Liu, F. Y.; Shan, X.-B.; Sheng, L. S. Ion-pair photodissociations of benzyl chloride through inner-valence electron excitations. Chemical Physics Letters 2010, 496: 254-256.

    Li, H.-B.; Tian, S. X.*; Yang, J. L. Propene oxidation on V4O11- cluster: Reaction dynamics to acrolein. Journal of Physical Chemistry A 2010, 114: 6542-6549.

    Mahmoodi-Darian, M.; Tian, S. X.; Denifl, S.*; Matejcik, S.; Maerk,T. D.; Scheier, P. Temperature dependence of electron attachment to 1-bromo-2-chlorobenzene and 1-bromo-3-chlorobenzene. International Journal of Mass Spectrometry 2010, 293: 51-55.

    Fu, C.-F.; Tian, S. X.* Molecular dynamics study of solvation differences between cis- and transplatin molecules in water. Journal of Chemical Physics 2010, 132: 174507 (7 pages). also selected by Virtual Journal of Biological Physics Research (May 15 issue, 2010) at http://www.vjbio.org

    Ko, Y. J.; Wang, H.; Cao, R.; Radisic, D.; Eustis, S. N.; Tian, S. X.*; Bowen, K. H.* Photoelectron spectroscopy of homogeneous nucleic acid base dimer anions. Physical Chemistry Chemical Physics 2010, 12: 3535-3541.

    * represents the corresponding author(s).

    Contact

    Department of Chemical Physics, USTC
    96 Jinzhai Road, Hefei City, Anhui 230026
    China
    Office Phone: (+86) 551 63606465
    Lab Phone: (+86) 551 63606744
    Email: sxtian@ustc.edu.cn

    分子立体反应动力学实验室

    研究组成员主要隶属于中国科技大学化学物理系,并依托合肥微尺度物质科学国家研究中心。目前的研究方向是气相分子的电子贴附解离和低能量离子碰撞反应动力学、液体(含溶液)的气液界面微观反应机制,以及用于四维透射电镜的超快相干电子束技术。 上述研究为大气化学、星际化学、生物分子结构、溶液化学合成等方面提供微观物理化学模型和先进技术。

    研究内容

    化学物质的起源 :星际空间中某些特殊分子、自由基、离子的产生和化学演化机制,行星(包括四万亿年前的地球)大气中氧气、水以及氨基酸、糖、核酸分子等生命相关基本物质的产生,分子手性的起源及其物理化学过程等。

    化学动力学奇异特征:微观反应的立体动力学和态-态动力学、反常同位素动力学效应、电子自旋和核自旋效应等。

    先进方法与技术:电子作为“催化剂”的化学反应新方法及其在有机与无机材料合成中的应用,超快量子相干电子束技术及其在电镜中的应用等。

    研究方法

    主要设备:电子-分子碰撞(贴附)解离的高分辨离子速度成像谱仪和光谱采集系统(自制)、离子-分子反应的离子速度成像谱仪(自制)、电子/离子与液体表面分子反应的质谱装置(自制)、针尖发射超快相干光电子系统(待研制)、四维透射电镜(待研制)。

    关键技术:低能量脉冲电子束(0-30eV、纳秒级脉冲宽度)、低能量脉冲离子束(0-60eV、纳秒-微秒脉冲宽度)、三维离子速度成像、微流喷射(microjet)液体束、芯片微流控反应器、时间延迟质谱、超快(102-3eV、飞秒-皮秒脉冲宽度)相干电子束。