Spectroscopic study on specific intermolecular interactions in aromatic biomolecules in the isolated state.

孤立状态下芳香族生物分子特定分子间相互作用的光谱研究。

• 批准号: 15350015
• 负责人: SEKIYA Hiroshi
• 金额: $ 8.32万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15350015/
• 关键词: biomolecules; hydrogen-bonded cluster; double-proton transfer; gas phase; electronic spectrum; picosecond time-resolved study; cooperative effect; dimer; 水素結合; 孤立状態; エキシトン相互作用; 7-アザインドールダイマー; プロトン移動; 超音速ジェット; トンネル効果; 励起状態ダイナミクス

Structures and the excited-state dynamics of hydrogen bonded molecules in supersonic jet expansion have been studied by both the frequency domain and time-domain measurements. We have measured hole-burning spectra of various deuterated isotomers of the hydrogen bonded 7-azaindole dimer. The spectra show that the exciton resonance interaction in the lowest excited state of the 7-azaindole dimer should be treated as a weak coupling limit of the exciton theory. The hole-burning spectra suggest that the vibronic states with short and long lifetimes are excited in the femtosecond time-resolved experiments by Zewail's group, providing bi-exponential decay profiles. The biexponential decay profiles had been a strong evidence of the stepwise excited-state double-proton transfer (ESDPT). However, we have found that the decay profiles excited by picoseond pulse are fitted with single-exponential functions. This result clearly shows that ESDPT occurs by the concerted mechanism. The dispersed fluo … More rescence spectra are measured for the undeuterated and deuterated 7-azaindole dimers. A remarkable H/D isotope effects on the reaction rate has been detected. We have found a cooperative nature of the ESDPT reaction.The effect of substitution on the ESDPT reaction has also been studied. The substitution of the methyl group at the 3-position of the 7-azaindole does not affect the ESDPT rate, but the substitution of the Cl atom or the dimethylamino group at the 4-position significantly decrease the ESDPT rate due to the weakening of the intermolecular hydrogen-bonds.We also measured various hydrogen bonded clusters in the neutral and ionic states to investigate the relation between the structure and dynamics. For example, we have examined the excited-state proton transfer of the 7-azaindole-(H_2O)_n(n=1-3). Previous report by Castleman et al. with femtosecond spectroscopy concluded that the excited-state proton transfer occurs in 7-azaindole-(H_20)_n(n=2-4). However, no red-shifted fluorescence has been observed in 7-azaindole-(H_2O)_n(n=1-3), indicating that the excited-state proton transfer is inhibited. Less

通过频域和时域测量研究了超音速射流膨胀中氢键分子的结构和激发态动力学。我们测量了氢键 7-氮杂吲哚二聚体的各种氘代异构体的烧孔光谱。光谱表明，7-氮杂吲哚二聚体最低激发态下的激子共振相互作用应被视为激子理论的弱耦合极限。烧孔光谱表明，在 Zewail 小组的飞秒时间分辨实验中，具有短寿命和长寿命的振动电子态被激发，提供了双指数衰变曲线。双指数衰变曲线是逐步激发态双质子转移（ESDPT）的有力证据。然而，我们发现皮秒脉冲激发的衰变曲线符合单指数函数。这个结果清楚地表明ESDPT是通过协调机制发生的。测量未氘化和氘化 7-氮杂吲哚二聚体的分散荧光光谱。已检测到 H/D 同位素对反应速率的显着影响。我们发现了 ESDPT 反应的协同性质。还研究了取代对 ESDPT 反应的影响。 7-氮杂吲哚3位甲基的取代并不影响ESDPT速率，但4位Cl原子或二甲氨基的取代由于分子间氢键的减弱而显着降低了ESDPT速率。我们还测量了中性和离子状态下的各种氢键簇，以研究结构和动力学之间的关系。例如，我们研究了 7-氮杂吲哚-(H_2O)_n(n=1-3) 的激发态质子转移。 Castleman 等人之前的报告。飞秒光谱得出激发态质子转移发生在7-氮杂吲哚-(H_20)_n(n=2-4)中。然而，在7-氮杂吲哚-(H_2O)_n(n=1-3)中没有观察到红移荧光，表明激发态质子转移受到抑制。较少的

项目成果

Excited-state double-proton transfer in the (3-methyl-7-azaindole)-(7-azaindole) hetero-dimer in the gas phase

• DOI: 10.1016/j.cplett.2005.02.087
• 发表时间: 2005-04-23
• 期刊: CHEMICAL PHYSICS LETTERS
• 影响因子: 2.8
• 作者: Komoto, Y;Sakota, K;Sekiya, H
• 通讯作者: Sekiya, H

Y.Honkawa et al.: "Infrared spectra and structures of aniline(+)-furan and aniline(+)-phenol. Preference between n-type and s-type hydrogen-bonded structures"Chemical Physics Letters. 376・1-2. 244-250 (2003)

Y. Honkawa等人：“苯胺(+)-呋喃和苯胺(+)-苯酚的红外光谱和结构。n型和s型氢键结构之间的偏好”化学物理快报376・1-2。 .244-250 (2003)

K.Sakota et al.: "Excited-state double-proton transfer dynamics of deuterated 7-azaindole dimers in a free jet studied by hole-burning spectroscopy"Physical Chemistry Chemical Physics. 6・1. 32-36 (2004)

K.Sakota 等：“通过烧孔光谱研究氘代 7-氮杂吲哚二聚体的激发态双质子转移动力学”，物理化学化学物理 6・1（2004 年）。

Excited-state double-proton transfer in the 7-azaindole dimer in the gas phase. 1.Evidence of complete localization in the lowest excited electronic state of asymmetric isotopomers

气相中 7-氮杂吲哚二聚体的激发态双质子转移。

• 发表时间: 2005
• 期刊: J.Phys.Chem.A 109(12)
• 作者: K.Sakota;H.Sekiya
• 通讯作者: H.Sekiya

Excited-state double-proton transfer in the 7-azaindole dimer in the gasphase. 2. Cooperative nature of double-proton transfer revealed by H/D kinetic isotopic effects

气相 7-氮杂吲哚二聚体中的激发态双质子转移。

• 发表时间: 2005
• 期刊: J.Phys.Chem.A 109
• 作者: K.Sakota;H.Sekiya
• 通讯作者: H.Sekiya