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飞秒时间分辨光电子影像技术和飞秒时间分辨质谱技术相结合, 研究了2-甲基吡嗪分子电子激发态超快非绝热弛豫动力学. 用323 nm光作为泵浦光, 把2-甲基吡嗪分子激发到第一激发态S1, 用400 nm光探测激发态演化过程. 通过时间分辨质谱技术测得S1态的寿命为98 ps. 实验中, 实时观察到了单重态S1向三重态T1的系间交叉过程. 通过分析发现, 跟吡嗪分子S1态的动力学过程不同, 2-甲基吡嗪分子激发到S1态后, 不仅S1 → T1系间交叉过程是S1态主要衰减通道, S1 → S0内转换过程也是S1态另一个主要衰减通道. 发挥飞秒时间分辨光电子影像技术的优点, 实验上得到不同泵浦-探测时间延迟的光电子角分布, 从角分布信息结合光电子能谱信息, 尝试观察2-甲基吡嗪分子的非绝热无场准直, 但由于2-甲基吡嗪分子对称性比吡嗪分子更低, 对称性更低分子准直现象的观察更有挑战性, 在实验中未能观察到非绝热准直动力学. 本工作为2-甲基吡嗪分子S1态非绝热弛豫动力学提供了较清楚的物理图像.The ultrafast nonadibatic relaxation dynamics of the excited state of 2-methylpyrazine has been studied by using femtosecond time-resolved photoelectron imaging and femtosecond time-resolved mass spectrometry. The first excited state S1 of 2-methylpyrazine was excited by 323 nm pump light, and the excited state deactivation process is detected by 400 nm probe light. The lifetime of S1 state 98 ps is obtained by time-resolved mass spectroscopy. The intersystem crossing from the S1 state to the T1 state is observed on real time. The relaxation dynamics of S1 state of 2-methlypyrazine is different from that of pyrazine, the results show that the intersystem crossing process between S1 and T1 is the main relaxation channel of S1 state of 2-methlypyrazine, but the internal conversion process between S1 and S0 is also a main relaxation channel of S1 state. By using the advantages of femtosecond time-resolved photoelectron imaging, the photoelectron angular distribution at different pump-probe time delay was obtained experimentally. From the photoelectron angle distribution combined with photoelectron kinetic energy distributions, we tried to observe the field-free nonadiabatic alignment. However, due to the fact that the molecular symmetry of 2-methylpyrazine is lower than that of pyrazine, it is more challenging to observe the phenomenon of molecular nonadiabatic alignment with lower symmetry. Therefore, it is fail to observe nonadiabatic alignment feature of 2-methylpyrazine in this experiment. This work provides a clearer physical picture for S1 state nonadibatic relaxation dynamics of 2-methylpyrazine.
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Keywords:
- Methlypyrazine /
- photoelectron imaging /
- intersystem crossing /
- pump-probe /
- time-resolved spectroscopy
[1] De Gruijl F 1999 Eur. J. Cancer 35 2003Google Scholar
[2] Ichihashi M, Ueda M, Budiyanto A, Bito T, Oka M, Fukunaga M, Tsuru K, Horikawa T 2003 Toxicology 189 21Google Scholar
[3] Iqbal A, Stavros V G 2010 J. Phys. Chem. Lett. 1 2274Google Scholar
[4] Domcke W, Stock G 1997 Adv. Chem. Phys. 100 1
[5] Gustavsson T, Improta R, Markovitsi D 2010 J. Phys. Chem. Lett. 1 2025Google Scholar
[6] Schoenlein R W, Peteanu L A, Mathies R, Shank C V 1991 Science 254 412Google Scholar
[7] Suzuki T, Wang L, Kohguchi H 1999 J. Chem. Phys. 111 4859Google Scholar
[8] Song J K, Tsubouchi M, Suzuki T 2001 J. Chem. Phys. 115 8810Google Scholar
[9] Ling F Z, Li S, Song X L, Wang Y M, Long J Y, Zhang B 2017 Sci. Rep. 7 15362Google Scholar
[10] Toshinori S 2014 Bull. Chem. Soc. Jpn. 87 341Google Scholar
[11] Farmanara P, Stert V, Radloff W, Hertel I V 2001 J. Phys. Chem. A 105 5613Google Scholar
[12] Suzuki Y I, Horio T, Fuji T, Suzuki T 2011 J. Chem. Phys. 134 184313Google Scholar
[13] Frad A, Lahmani F, Tramer A, Tric C 1974 J. Chem. Phys. 60 4419Google Scholar
[14] Zhong D, Diau E W G, Bernhardt T M, Feyter S D, Roberts J D, Zewail A H 1998 Chem. Phys. Lett. 298 129Google Scholar
[15] Wang L, Kohguchi H, Suzuki T 1999 Faraday Discuss. 113 37Google Scholar
[16] Tsubouchi M, Whitaker B J, Wang L, Kohguchi H, Suzuki T 2001 Phys. Rev. Lett. 86 4500Google Scholar
[17] 刘玉柱, 肖韶荣, 王俊锋, 何仲福, 邱学军, Gregor Knopp 2016 物理学报 65 113301Google Scholar
Liu Y Z, Xiao S R, Wang J F, He Zhong F, Qiu X J, Knopp G 2016 Acta Phys. Sin. 65 113301Google Scholar
[18] 刘玉柱, 陈云云, 郑改革, 金峰Gregor, Knopp 2016 物理学报 65 053302Google Scholar
Liu Y Z, Chen Y Y, Zheng G G, Jin F, Knopp G 2016 Acta Phys. Sin. 65 053302Google Scholar
[19] Liu Y Z, Knopp G, Qin C C, Gerber T 2015 Chem. Phys. 446 142Google Scholar
[20] Fuji T, Suzuki Y I, Horio T, Suzuki T, Mitrić R, Werner U, Koutecký V B 2010 J. Chem. Phys. 133 234303Google Scholar
[21] 凌丰姿 2018 博士学位论文(武汉: 中国科学院武汉物理与数学研究所)
Ling F Z 2018 Ph. D. Dissertation (Wuhan: Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences) (in Chinese)
[22] Hao Q L, Long J Y, Deng X L, Tang Y, Abulimiti B, Zhang B 2017 J. Phys. Chem. A 121 3858Google Scholar
[23] Ling F, Li S, Wei J, Liu K, Wang Y M, Zhang B 2018 J. Chem. Phys. 148 144311Google Scholar
[24] Dribinski V, Ossadtchi A, Mandelshtam V. A, Reisler H 2002 Rev. Sci. Instrum. 73 2634Google Scholar
[25] Matsumoto Y, Kim S. K, Suzuki T 2003 J. Chem. Phys. 119 300Google Scholar
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图 1 (a)光电子影像装置实物图; (b)飞秒时间分辨光电子影像装置示意图[21]
Fig. 1. (a) Photoelectron imaging apparatus; (b) schematic diagram of the femtosecond time resolved photoelectron imaging setup.
图 2 (a)泵浦光323 nm, 探测光400 nm的各自单光和零时刻双光质谱;(b)泵浦光323 nm, 探测光400 nm作用下时间分辨母体离子信号, 图中实线表示拟合曲线, 圆圈代表实验数据
Fig. 2. (a) Two color (at time overlap) and one color mass spectra of 2-methlypyrazine at 323 nm pump and 400 nm probe; (b) time-resolved total ion signals of parent ion as a function of delay time between the pump pulse at 323 nm and the probe pulse at 400 nm. The circles are the experimental results, and solid lines are the fitting results.
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[1] De Gruijl F 1999 Eur. J. Cancer 35 2003Google Scholar
[2] Ichihashi M, Ueda M, Budiyanto A, Bito T, Oka M, Fukunaga M, Tsuru K, Horikawa T 2003 Toxicology 189 21Google Scholar
[3] Iqbal A, Stavros V G 2010 J. Phys. Chem. Lett. 1 2274Google Scholar
[4] Domcke W, Stock G 1997 Adv. Chem. Phys. 100 1
[5] Gustavsson T, Improta R, Markovitsi D 2010 J. Phys. Chem. Lett. 1 2025Google Scholar
[6] Schoenlein R W, Peteanu L A, Mathies R, Shank C V 1991 Science 254 412Google Scholar
[7] Suzuki T, Wang L, Kohguchi H 1999 J. Chem. Phys. 111 4859Google Scholar
[8] Song J K, Tsubouchi M, Suzuki T 2001 J. Chem. Phys. 115 8810Google Scholar
[9] Ling F Z, Li S, Song X L, Wang Y M, Long J Y, Zhang B 2017 Sci. Rep. 7 15362Google Scholar
[10] Toshinori S 2014 Bull. Chem. Soc. Jpn. 87 341Google Scholar
[11] Farmanara P, Stert V, Radloff W, Hertel I V 2001 J. Phys. Chem. A 105 5613Google Scholar
[12] Suzuki Y I, Horio T, Fuji T, Suzuki T 2011 J. Chem. Phys. 134 184313Google Scholar
[13] Frad A, Lahmani F, Tramer A, Tric C 1974 J. Chem. Phys. 60 4419Google Scholar
[14] Zhong D, Diau E W G, Bernhardt T M, Feyter S D, Roberts J D, Zewail A H 1998 Chem. Phys. Lett. 298 129Google Scholar
[15] Wang L, Kohguchi H, Suzuki T 1999 Faraday Discuss. 113 37Google Scholar
[16] Tsubouchi M, Whitaker B J, Wang L, Kohguchi H, Suzuki T 2001 Phys. Rev. Lett. 86 4500Google Scholar
[17] 刘玉柱, 肖韶荣, 王俊锋, 何仲福, 邱学军, Gregor Knopp 2016 物理学报 65 113301Google Scholar
Liu Y Z, Xiao S R, Wang J F, He Zhong F, Qiu X J, Knopp G 2016 Acta Phys. Sin. 65 113301Google Scholar
[18] 刘玉柱, 陈云云, 郑改革, 金峰Gregor, Knopp 2016 物理学报 65 053302Google Scholar
Liu Y Z, Chen Y Y, Zheng G G, Jin F, Knopp G 2016 Acta Phys. Sin. 65 053302Google Scholar
[19] Liu Y Z, Knopp G, Qin C C, Gerber T 2015 Chem. Phys. 446 142Google Scholar
[20] Fuji T, Suzuki Y I, Horio T, Suzuki T, Mitrić R, Werner U, Koutecký V B 2010 J. Chem. Phys. 133 234303Google Scholar
[21] 凌丰姿 2018 博士学位论文(武汉: 中国科学院武汉物理与数学研究所)
Ling F Z 2018 Ph. D. Dissertation (Wuhan: Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences) (in Chinese)
[22] Hao Q L, Long J Y, Deng X L, Tang Y, Abulimiti B, Zhang B 2017 J. Phys. Chem. A 121 3858Google Scholar
[23] Ling F, Li S, Wei J, Liu K, Wang Y M, Zhang B 2018 J. Chem. Phys. 148 144311Google Scholar
[24] Dribinski V, Ossadtchi A, Mandelshtam V. A, Reisler H 2002 Rev. Sci. Instrum. 73 2634Google Scholar
[25] Matsumoto Y, Kim S. K, Suzuki T 2003 J. Chem. Phys. 119 300Google Scholar
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