Construction of Simultaneous Observation System of Time-Resolved ESR and Nanosecond Transient Absorption Spectra

时间分辨ESR与纳秒瞬态吸收光谱同步观测系统的构建

• 批准号: 63840012
• 负责人: TERO Shozo
• 金额: $ 8.32万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63840012/
• 关键词: Time-resolved ESR; Nanosecond spectroscopy; Transient absorption; Laser photolysis; Photochemistry; レーザブラッシュフォトリシス; 過渡吸収スペクトル

A nanosecond laser photolysis system and an optical transmission cavity for time-resolved ESR spectroscopy were constructed. We applied the system for several photochemical reactions to measure transient absorption and time-resolved ESR spectra of the short-lived intermediates. The present study clearly shows that this system plays an important role in photochemistry, since the informations obtained from these spectra are complements each of the other.1. Nanosecond laser photolysis system. For measurements of transient absorption spectra of the short-lived excited triplet states and radical intermediates generated from laser excitation, a nanosecond laser photolysis system was constructed. We obtained desired capability for our purpose.2. Transmission microwave cavity. We prepared a transmission cavity equipping with a window (5 phi) for laser photolysis. Unloaded Q value is large than 3000. The cavity is able to connect to the transition absorption spectroscopy by optical fibers.3. Ph … More otochemical studies on the reaction mechanism and dynamics. Photochemistry of epoxyketbne derivatives was studied in the presence of electron or hydrogen donating reagents. In the presence of amines, the anion radical of epoxyketone was observed by transient absorption method. The life-time of the radical was determined to be less than 1mus. Although the carbon centered radical generated from the ring opening was not detected by the transient absorption method, it was clearly measured by time-resolved ESR spectroscopy. Therefore, we can determine the photochemical chain reaction mechanism by using the present system.When free radical shows second order decay, it is usually difficult to determine the molar extinction coefficient. The present system is very useful for the purpose. We can determine the extinction coefficients of shortlived pyridinyl radicals generated from the laser photolysis of the photosensitive dimers. The time-resolved triplet-triplet absorption spectrum of o-nitrobiphenyl was also observed. Less

建立了用于时间分辨ESR谱的纳秒激光光解系统和光透射腔。我们将该系统应用于几个光化学反应，以测量瞬态吸收和时间分辨ESR光谱的短寿命的中间体。本研究清楚地表明，该系统在光化学中起着重要的作用，因为从这些光谱中获得的信息是相互补充的。纳秒激光光解系统。为了测量激光激发产生的短寿命激发三重态和自由基中间体的瞬态吸收光谱，构建了纳秒激光光解系统。我们获得了达到目的所需的能力。传输微波腔。我们制备了一个带有窗口（5 φ）的激光光解传输腔。空载Q值大于3000。该腔能够通过光纤连接到跃迁吸收光谱。3. pH ...更多信息 反应机理和动力学的光化学研究。本文研究了在供电子或供氢试剂存在下环氧酮衍生物的光化学。在胺存在下，用瞬态吸收法观察到环氧酮的阴离子自由基。自由基的寿命小于1 μ s。虽然从开环产生的碳为中心的自由基没有检测到的瞬态吸收法，它是清楚地测量时间分辨ESR光谱。当自由基呈二级衰减时，通常很难确定其摩尔消光系数。目前的系统在这方面非常有用。我们可以确定从光敏二聚体的激光光解产生的短寿命的吡啶基自由基的消光系数。还观察到邻硝基联苯的时间分辨三重态-三重态吸收光谱。少

项目成果

S.Tero-Kubota, K.Akiyama, T.Ikoma, and Y.Ikegami: "Time-Resolved EPR Studies on the Photochemical Hydrogen Abstraction Reactions and the Excited Triplet States of 4-Substituted Pyridines" J. Phys. Chem. 1990.

S.Tero-Kubota、K.Akiyama、T.Ikoma 和 Y.Ikegami：“4-取代吡啶光化学夺氢反应和激发三重态的时间分辨 EPR 研究”J. Phys。

S.Tero-Kubota,K.Akiyama,T.Ikoma,and Y.Ikegami: "Time-Resolved EPR Studies on the Photochemical Hydrogen Abstraction Reactions and the Excited Triplet States of 4-Substituted Pyridines" J.Phys.Chem.投稿中. (1990)

S.Tero-Kubota、K.Akiyama、T.Ikoma 和 Y.Ikegami：“4-取代吡啶的光化学夺氢反应和激发三重态的时间分辨 EPR 研究”提交给 J.Phys.Chem。 (1990)

T.Ikoma, K.Akiyama, S.Tero-Kubota, and Y.Ikegami: "CIDEP Spectra Observed from Photochemical Reactions of Some Aromatic Carbonyl Compounds" Chem. Lett. 1990.

T.Ikoma、K.Akiyama、S.Tero-Kubota 和 Y.Ikegami：“从某些芳香族羰基化合物的光化学反应中观察到的 CIDEP 光谱” Chem。

K.Akiyama,A.Kaneko,S.Tero-Kubota,and Y.Ikegami: "Spin Polarization Conservation during Triplet-Triplet Energy Transfer in Fluid Solution As Studied by Time-Resolved ESR Spectroscopy" J.Am.Chem.Soc.112. (1990)

K.Akiyama、A.Kaneko、S.Tero-Kubota 和 Y.Ikegami：“通过时间分辨 ESR 光谱研究流体溶液中三重态-三重态能量转移过程中的自旋极化守恒”J.Am.Chem.Soc.112

K.Akiyama,A.Kaneko,S.Tero-Kubota,and Y.Ikegami: "Spin Polarization Conservation during Triplet-Triplet Energy Transfer in Fluid Solution As Studied by Time-Resolved ESR Spectroscopy" J.Am.Chem.Soc.印刷中. 112. (1990)

K.Akiyama、A.Kaneko、S.Tero-Kubota 和 Y.Ikegami：“通过时间分辨 ESR 光谱研究流体溶液中三重态-三重态能量转移过程中的自旋极化守恒”J.Am.Chem.Soc.Printed 112.（1990）