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Lee YR, Kwon CH. Determination of highest occupied molecular orbital and cationic structures of cyclopentanone using high‐resolution vacuum ultraviolet mass‐analyzed threshold ionization mass spectrophotometry. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yu Ran Lee
- Department Forensic Chemistry Division National Forensic Service Wonju Republic of Korea
| | - Chan Ho Kwon
- Department of Chemistry Kangwon National University Chuncheon Republic of Korea
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Wang Y, Wei J, Cao L, Zhang B, Zhang S. The ultrafast nonradiative processes and photodissociation dynamics investigation of S1 state in propanal. J Chem Phys 2022; 156:074306. [DOI: 10.1063/5.0077490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Yanmei Wang
- Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology CAS, China
| | - Jie Wei
- Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences, China
| | - Ling Cao
- Innovation Academy for Precision Measurement Science and Technology CAS, China
| | - Bing Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences, China
| | - Song Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences, China
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Wang Y, Gu Z, Deng X, Zhang B. Ultraviolet-light-triggered isomerization of Rydberg-excited propanal: Real-time capture of ultrafast structural evolution and dynamics investigation. J Chem Phys 2021; 154:054301. [PMID: 33557549 DOI: 10.1063/5.0039802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Structure rearrangement processes, such as isomerization, are attracting extensive interest as a potential carrier in molecular scale electronics design. UV-light-triggered isomerization of Rydberg-excited propanal with two UV photons has been investigated with time-resolved photoelectron spectroscopy. By following the photoionization from 3s Rydberg states in the time domain, the ultrafast structural evolution and the corresponding photoisomerization dynamics are observed and tracked in real-time. The conversion barrier for isomerization from cis-propanal to gauche isomer is estimated to be about 1500 ± 100 cm-1 experimentally. Both the photoisomerization yield and the conversion rate have shown strong dependence on the excitation energy. It is observed that whether vibration modes are selectively excited or not, cis-to-gauche photoisomerization of propanal in 3s Rydberg state occurs once the excitation energy is higher than the conversion barrier without any vibrational excitation specificity. This yields a powerful approach to studying structural evolution dynamics in large molecules, which may have applications in molecular devices.
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Affiliation(s)
- Yanmei Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China
| | - Zhenfei Gu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China
| | - Xulan Deng
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China
| | - Bing Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China
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Hricovíni M, Asher J, Hricovíni M. Photochemical anti- syn isomerization around the -N-N[double bond, length as m-dash] bond in heterocyclic imines. RSC Adv 2020; 10:5540-5550. [PMID: 35497446 PMCID: PMC9049245 DOI: 10.1039/c9ra10730d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 01/28/2020] [Indexed: 11/21/2022] Open
Abstract
EPR and NMR experiments on a quinazolinone-based Schiff's base in DMSO solution showed that irradiation with UV light (365 nm) leads to photochemically-induced isomerization from the anti- to the higher-energy syn-form around the -N-N[double bond, length as m-dash] linkage. The anti- to syn-isomerization was relatively fast, and the maximum amount of conversion detected (25%) was reached within 10 min; thermodynamic equilibrium re-established itself in about 15 min. DFT calculations were performed on the investigated compound and small model systems, and reproduced the experimental fact of the anti-conformer being lower in energy than the syn. Theoretical analysis of excited states, including visualisation of natural transition orbitals, identified possible pathways for syn-anti isomerisation, although the details vary with π-system size, making the use of small models of limited utility. The investigated compound probably isomerises through the third singlet excited state (S3), a π-π* excitation, relaxing through S2, also a π-π* state.
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Affiliation(s)
- Michal Hricovíni
- Institute of Chemistry, Slovak Academy of Sciences Dúbravská cesta 9 845 38 Bratislava Slovak Republic
| | - James Asher
- Institute of Inorganic Chemistry, Slovak Academy of Sciences Dúbravská cesta 9 845 36 Bratislava Slovak Republic
| | - Miloš Hricovíni
- Institute of Chemistry, Slovak Academy of Sciences Dúbravská cesta 9 845 38 Bratislava Slovak Republic +421-2-5940222 +421-2-59410323
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Hao Q, Deng X, Long J, Wang Y, Abulimiti B, Zhang B. Real-time observation of cascaded electronic relaxation processes in p-Fluorotoluene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 183:109-115. [PMID: 28441538 DOI: 10.1016/j.saa.2017.04.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 03/31/2017] [Accepted: 04/17/2017] [Indexed: 06/07/2023]
Abstract
Ultrafast electronic relaxation processes following two photoexcitation of 400nm in p-Fluorotoluene (pFT) have been investigated utilizing time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. Cascaded electronic relaxation processes started from the electronically excited S2 state are directly imaged in real time and well characterized by two distinct time constants of ~85±10fs and 2.4±0.3ps. The rapid component corresponds to the lifetime of the initially excited S2 state, including the structure relaxation from the Franck-Condon region to the conical intersection of S2/S1 and the subsequent internal conversion to the highly excited S1 state. While, the slower relaxation constant is attributed to the further internal conversion to the high levels of S0 from the secondarily populated S1 locating in the channel three region. Moreover, dynamical differences with benzene and toluene of analogous structures, including, specifically, the slightly slower relaxation rate of S2 and the evidently faster decay of S1, are also presented and tentatively interpreted as the substituent effects. In addition, photoelectron kinetic energy and angular distributions reveal the feature of accidental resonances with low-lying Rydberg states (the 3p, 4s and 4p states) during the multi-photon ionization process, providing totally unexpected but very interesting information for pFT.
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Affiliation(s)
- Qiaoli Hao
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Xulan Deng
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Jinyou Long
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yanmei Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Bumaliya Abulimiti
- College of Physics and Electronic Engineering, Xinjiang Normal University, Urumqi 830054, PR China.
| | - Bing Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
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Hall AJ, Roche SP, West LM. Synthesis of Briarane Diterpenoids: Biomimetic Transannular Oxa-6π electrocyclization Induced by a UVA/UVC Photoswitch. Org Lett 2017; 19:576-579. [PMID: 28080074 DOI: 10.1021/acs.orglett.6b03689] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A biomimetic synthesis of briareolate ester B (3) from briareolate ester L (1) via the intermediate briareolate ester G (2) has been achieved through a unique transannular oxa-6π electrocyclization induced by UVA light. UVC irradiation of 3 triggered a rapid retro-6π electrocyclization to establish an unprecedented photochromic switch. In the ground state, reaction of 1 led to the formation of a polycyclic γ-spiroketal γ-lactone 5, architecturally related to the ether-bridged cembranoids of the cladiellin class.
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Affiliation(s)
- Andrew J Hall
- Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States
| | - Stéphane P Roche
- Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States
| | - Lyndon M West
- Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431, United States
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Zuo W, Yin H, Liu X, Lv H, Zhao L, Shi Y, Yan B, Jin M, Ding D, Xu H. Identification of the cationic excited state of cyclopentanone via time-resolved Ion yield measurements. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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