1
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Bodi A, Knurr J, Ascher P, Hemberger P, Bostedt C, Al Haddad A. VUV absorption spectra of water and nitrous oxide by a double-duty differentially pumped gas filter. JOURNAL OF SYNCHROTRON RADIATION 2024; 31:1257-1263. [PMID: 39042580 PMCID: PMC11371026 DOI: 10.1107/s1600577524005423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 06/06/2024] [Indexed: 07/25/2024]
Abstract
The differentially pumped rare-gas filter at the end of the VUV beamline of the Swiss Light Source has been adapted to house a windowless absorption cell for gases. Absorption spectra can be recorded from 7 eV to up to 21 eV photon energies routinely, as shown by a new water and nitrous oxide absorption spectrum. By and large, the spectra agree with previously published ones both in terms of resonance energies and absorption cross sections, but that of N2O exhibits a small shift in the {\tilde{\bf D}} band and tentative fine structures that have not yet been fully described. This setup will facilitate the measurement of absorption spectra in the VUV above the absorption edge of LiF and MgF2 windows. It will also allow us to carry out condensed-phase measurements on thin liquid sheets and solid films. Further development options are discussed, including the recording of temperature-dependent absorption spectra, a stationary gas cell for calibration measurements, and the improvement of the photon energy resolution.
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Affiliation(s)
- Andras Bodi
- Paul Scherrer Institute5232Villigen-PSISwitzerland
| | - Jonas Knurr
- Paul Scherrer Institute5232Villigen-PSISwitzerland
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2
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Wang Y, Zhao Y, Zhang N, Wang W, Hu L, Luo C, Yuan D, Zhou X, Parker DH, Yang X, Wang X. Vibrational state-specific nonadiabatic photodissociation dynamics of OCS+ via A2Π1/2 (ν1 0 ν3) states. J Chem Phys 2024; 160:084301. [PMID: 38385514 DOI: 10.1063/5.0191893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 01/29/2024] [Indexed: 02/23/2024] Open
Abstract
The identification and analysis of quantum state-specific effects can significantly deepen our understanding of detailed photodissociation dynamics. Here, we report an experimental investigation on the vibrational state-mediated photodissociation of the OCS+ cation via the A2Π1/2 (ν1 0 ν3) states by using the velocity map ion imaging technique over the photolysis wavelength range of 263-294 nm. It was found that the electronically excited S+ product channel S+(2Du) + CO (X1Σ+) was significantly enhanced when the ν1 and ν3 vibrational modes were excited. Clear deviations in the branching ratios of the electronically excited S+ channel were observed when the vibrational modes ν1 and ν3 were selectively excited. The results reveal that vibrationally excited states play a vital role in influencing the nonadiabatic couplings in the photodissociation process.
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Affiliation(s)
- Yaling Wang
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yunfan Zhao
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Ning Zhang
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Wenxin Wang
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Liru Hu
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Chang Luo
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Daofu Yuan
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Xiaoguo Zhou
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - David H Parker
- Department of Molecular and Laser Physics, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Department of Chemistry, School of Science, Southern University of Science and Technology, Shenzhen 518055, China
- Hefei National Laboratory, Hefei 230088, China
| | - Xingan Wang
- Hefei National Research Center for Physical Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, Hefei 230088, China
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3
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Qureishy T, Løyland S, Jørgensen SJ, Færgestad EM, Norby T, Uggerud E. Mechanisms for sonochemical oxidation of nitrogen. Phys Chem Chem Phys 2022; 24:15357-15364. [PMID: 35703372 DOI: 10.1039/d2cp01995g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
N2O, and mixtures of N2 and O2, dissolved in water-both in the presence and absence of added noble gases-have been subjected to ultrasonication with quantification of nitrite and nitrate products. Significant increase in product formation upon adding noble gas for both reactant systems is observed, with the reactivity order Ne < Ar < Kr < Xe. These observations lend support to the idea that extraordinarily high electronic and vibrational temperatures arise under these conditions. This is based on recent observations of sonoluminescence in the presence of noble gases and is inconsistent with the classical picture of adiabatic bubble collapse upon acoustic cavitation. The reaction mechanisms of the first few reaction steps necessary for the critical formation of NO are discussed, illustrated by quantum chemical calculations. The role of intermediate N2O in this series of elementary steps is also discussed to better understand the difference between the two reactant sources (N2O and 2 : 1 N2 : O2; same stoichiometry).
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Affiliation(s)
- Thomas Qureishy
- Department of Chemistry, University of Oslo, Norway. .,Centre for Materials Science and Nanotechnology, University of Oslo, Norway
| | - Sverre Løyland
- Department of Chemistry, University of Oslo, Norway. .,Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, Norway
| | - Susanne J Jørgensen
- Department of Chemistry, University of Oslo, Norway. .,Centre for Biogeochemistry in the Anthropocene, University of Oslo, Norway
| | - Eline M Færgestad
- Department of Chemistry, University of Oslo, Norway. .,Centre for Biogeochemistry in the Anthropocene, University of Oslo, Norway
| | - Truls Norby
- Department of Chemistry, University of Oslo, Norway. .,Centre for Materials Science and Nanotechnology, University of Oslo, Norway
| | - Einar Uggerud
- Department of Chemistry, University of Oslo, Norway. .,Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, Norway
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Zhao M, Li ZX, Xie T, Chang Y, Wu FY, Wang Q, Chen WT, Wang T, Wang XA, Yuan KJ, Yang XM. Photodissociation dynamics of CS 2 near 204 nm: The S( 3P J)+CS( X1Σ +) channels. CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2010183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Min Zhao
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Zhen-xing Li
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Ting Xie
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Yao Chang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Fu-yan Wu
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Qin Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Wen-tao Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Tao Wang
- College of Science, Sothern University of Science and Technology, Shenzhen 518055, China
| | - Xing-an Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Kai-jun Yuan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xue-ming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- College of Science, Sothern University of Science and Technology, Shenzhen 518055, China
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5
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Wang SW, Yuan DF, Chen WT, Tang L, Yu SR, Yang XM, Wang XA. Photodissociation dynamics of OCS near 128 nm: S(3PJ=2,1,0), S(1D2) and S(1S0) channels. CHINESE J CHEM PHYS 2020. [DOI: 10.1063/1674-0068/cjcp1911179] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Si-wen Wang
- Hefei National Laboratory for Materials Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Dao-fu Yuan
- Hefei National Laboratory for Materials Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Wen-tao Chen
- Hefei National Laboratory for Materials Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Ling Tang
- Hefei National Laboratory for Materials Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Sheng-rui Yu
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou 311231, China
| | - Xue-ming Yang
- State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- School of Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xing-an Wang
- Hefei National Laboratory for Materials Science at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
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Yu S, Yuan D, Chen W, Zhou J, Yang X, Wang X. Vacuum ultraviolet photodissociation dynamics of CO 2 near 133 nm: The spin-forbidden O( 3P j=2,1,0) + CO(X 1Σ +) channel. J Chem Phys 2019; 151:214306. [PMID: 31822085 DOI: 10.1063/1.5129764] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Understanding vacuum ultraviolet (VUV) photodissociation dynamics of CO2 is of considerable importance in the study of atmospheric chemistry and planetary chemistry. Yet, photodissociation dynamics of the spin-forbidden O(3Pj=2,1,0) + CO(X1Σ+) channel has not been clearly understood so far. Here, we study the O(3Pj) + CO(X1Σ+) dissociation processes in the VUV photodissociation of CO2 at the photolysis wavelengths between 129.02 and 134.67 nm by using the time-sliced velocity-mapped ion imaging technique. From the vibrational-resolved images of the O(3Pj=2,1,0) photofragment, the total kinetic energy releases, the CO(X1Σ+) cofragment vibrational state distributions, and the product angular distributions have been derived, respectively. The experimental observations show that the total kinetic energy releases for the three 3Pj spin-orbit states (j = 2, 1, 0) exhibit a broad CO(X1Σ+) vibrational energy distribution with significant inverted characteristics, especially at short photoexcitation wavelengths, indicating that the VUV photodissociation could take place in a relatively linear geometry of the triplet state, with one C-O bond extended and the other compressed. Furthermore, a notable photolysis wavelength dependent feature has also been found in the product angular distributions of all three spin-orbit channels (j = 2, 1, 0): Only the vibrational-state specific anisotropy parameter β values at 130.18 nm behave more anisotropic, while all those at other photolysis wavelengths are near the value β = 0.5 for O(3Pj=2,1) channels or β = 0.25 for the O(3Pj=0) channel, with small fluctuations. This anomalous phenomenon suggests that the different nonadiabatic interactions, such as singlet-triplet coupling, may play a key role in the formation of O(3Pj=2,1,0) + CO(X1Σ+) products, with strong photolysis wavelength dependence.
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Affiliation(s)
- Shengrui Yu
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang Province, People's Republic of China
| | - Daofu Yuan
- Center for Advanced Chemical Physics and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, Anhui Province, People's Republic of China
| | - Wentao Chen
- Center for Advanced Chemical Physics and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, Anhui Province, People's Republic of China
| | - Jiami Zhou
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang Province, People's Republic of China
| | - Xueming Yang
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou 311231, Zhejiang Province, People's Republic of China
| | - Xingan Wang
- Center for Advanced Chemical Physics and Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, Anhui Province, People's Republic of China
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7
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Chen W, Zhang L, Yuan D, Chang Y, Yu S, Wang S, Wang T, Jiang B, Yuan K, Yang X, Wang X. Observation of the Carbon Elimination Channel in Vacuum Ultraviolet Photodissociation of OCS. J Phys Chem Lett 2019; 10:4783-4787. [PMID: 31378065 DOI: 10.1021/acs.jpclett.9b01811] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The textbook mechanism for OCS photodissociation mainly involves the CO + S or CS + O product channel via a single bond fission. However, a third dissociation channel concerning the cleavage of both C-S and C-O bonds yielding SO + C products, though thermodynamically allowed, has never been verified experimentally to date. By using a tunable vacuum ultraviolet laser light and time-sliced velocity map ion imaging technique, we have clearly observed the SO(X3Σ-) + C(3PJ=0) products as the vacuum ultraviolet laser photon energy gradually exceeds its thermodynamic threshold. The corresponding SO(X3Σ-) coproducts are highly vibrationally excited and show varying angular distributions from isotropic to anisotropic as the excitation photon energy increases. Theoretical analysis suggests that a fast nonadiabatic pathway plays a dominant role in the formation of the anisotropic SO products. That isotropic products arise as the excitation photon energies approach the thermodynamic threshold can be reasonably explained by the "roaming mechanism".
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Affiliation(s)
- Wentao Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Liang Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Daofu Yuan
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yao Chang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Shengrui Yu
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, Hangzhou 311231, China
| | - Siwen Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Tao Wang
- Department of Chemistry, School of Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Bin Jiang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Kaijun Yuan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Department of Chemistry, School of Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xingan Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
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8
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Gao H, Ng CY. Quantum state-to-state vacuum ultraviolet photodissociation dynamics of small molecules. CHINESE J CHEM PHYS 2019. [DOI: 10.1063/1674-0068/cjcp1812290] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Hong Gao
- Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Cheuk-Yiu Ng
- Department of Chemistry, University of California, Davis CA 95616, USA
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9
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Yu S, Yuan D, Chen W, Xie T, Zhou J, Wang T, Chen Z, Yuan K, Yang X, Wang X. Vacuum ultraviolet photodissociation dynamics of N 2O via the C 1Π state: The N( 2D j=5/2, 3/2) + NO(X 2Π) product channels. J Chem Phys 2018; 149:104309. [PMID: 30219012 DOI: 10.1063/1.5042627] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We study the vacuum ultraviolet photodissociation dynamics of N2O via the C1Π state by using the time-sliced velocity map ion imaging technique. Images of N(2Dj=5/2, 3/2) products from the N atom elimination channels were acquired at a set of photolysis wavelengths from 142.55 to 148.19 nm. Vibrational states of the NO(X2Π) co-fragments were partially resolved in experimental images. From these images, the product total kinetic energy release distributions (TKERs), branching ratios of the vibrational states of NO(X2Π) co-fragments, and the vibrational state specific angular anisotropy parameters (β) have been determined. Notable features were found in the experimental results: the TKERs show that the NO(X2Π) co-fragments are highly vibrationally excited. For the highly vibrationally excited state of NO(X2Π), a bimodal rotational structure is found at all the studied photolysis wavelengths. Furthermore, the vibrational state specific β values of both spin-orbit channels (j = 3/2, 5/2) clearly show a monotonic decrease as the vibrational quantum number of NO(X2Π) increases. These observations suggest that multiple dissociation pathways play a role in the formation of the N(2Dj=5/2, 3/2) + NO(X2Π) products: one corresponds to a fast dissociation pathway through the linear state (the C1Π state) following the initial excitation to a slightly bent geometry in the vicinity of the linear C1Π configuration, leading to the low rotationally excited components with relatively large β values; the other corresponds to a relatively slow dissociation pathway through the bent C(31A') or C(31A″) state, leading to moderately rotationally excited NO(X2Π) products with smaller β values.
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Affiliation(s)
- Shengrui Yu
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou, Zhejiang 311231, People's Republic of China
| | - Daofu Yuan
- Center for Advanced Chemical Physics (iChEM, Collaborative Innovation Center of Chemistry for Energy Materials), Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
| | - Wentao Chen
- Center for Advanced Chemical Physics (iChEM, Collaborative Innovation Center of Chemistry for Energy Materials), Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
| | - Ting Xie
- Center for Advanced Chemical Physics (iChEM, Collaborative Innovation Center of Chemistry for Energy Materials), Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
| | - Jiami Zhou
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou, Zhejiang 311231, People's Republic of China
| | - Tao Wang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, People's Republic of China
| | - Zhichao Chen
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, People's Republic of China
| | - Kaijun Yuan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, People's Republic of China
| | - Xueming Yang
- Hangzhou Institute of Advanced Studies, Zhejiang Normal University, 1108 Gengwen Road, Hangzhou, Zhejiang 311231, People's Republic of China
| | - Xingan Wang
- Center for Advanced Chemical Physics (iChEM, Collaborative Innovation Center of Chemistry for Energy Materials), Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
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