Development of molecular spectroscopy with the use of femtosecond light pulses in the near-infrared spectral region

利用近红外光谱区飞秒光脉冲发展分子光谱

基本信息

批准号：
15350005
负责人：
IWATA Koichi
金额：
$ 9.86万
依托单位：
The University of Tokyo
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-15350005/
关键词：
femtosecond time-resolved near-infrared spectroscopy electron-transfer reaction bianthryl titanium oxide 偏光測定

项目摘要

1. Formation of charge-transfer state in bianthrylBianthryl is formed by two anthracene rings connected by a C-C bond. When this molecule absorbs a photon, an electron is migrated from one of the anthracene rings to the other. This is one of the most basic and simplest chemical reactions. By using femtosecond time-resolved near-infrared spectroscopy, the locally excited (LE) state and the charge transfer (CT) state are clearly observed as separate transitions. It has been concluded that the LE state generated by the photoirradiation of bianthryl in acetonitrile solution is directly converted to the CT state.2.Carrier dynamics in titanium oxideBecause the wavelength of the probe light is longer than visible or ultraviolet spectroscopies, it is possible to apply time-resolved near-infrared spectroscopy to scattering samples with the transmission method. By using this advantage, the head investigator and his collaborators have applied femtosecond time-resolved near-infrared spectroscopy t … More o the powder samples of titanium oxide photocatalyst (TIO4, 20 nm in diameter). They successfully observed an electron relaxation process that occurs within 1 ps, electro-hole recombination processes in several tens of picoseconds, and an electron migration process from titanium oxide to platinum co-catalyst in 2 ps. The results explain the mechanism of the increase of catalytic activities when platinum co-catalyst is loaded to titanium oxide particles.3.Nature of charge-transfer state of symmetrically and asymmetrically substituted bianthrylsTime-resolved near-infrared spectra of symmetrically and asymmetrically substituted bianthryls have been measured. CT state absorption bands in the near-infrared region were observed only for the symmetrically substituted bianthryls ; they were not observed for the asymmetrically substituted bianthryls. It is strongly suggested that the CT absorption band observed in the near-infrared region represents the charge resonance interaction between the two anthracene rings. Less

1。双乙烯二酯中电荷转移状态的形成是由C-C键相连的两个蒽环形成的。当该分子吸收光子时，电子将从蒽环之一迁移到另一个环。这是最基本，最简单的化学反应之一。通过使用飞秒时间分辨的近红外光谱，清楚地将局部激发（LE）状态和电荷转移（CT）状态清楚地观察到是单独的过渡。得出的结论是，乙腈溶液中双乙烯的光辐射产生的LE状态直接转换为CT状态。2。氧化钛的载体动力学探头光的波长比可见光或紫外线光谱的探针的波长更长，因此可以将近乎定位的谱图应用于近方频谱的传播。通过利用这一优势，首席研究员及其合作者应用了飞秒时间分辨的近红外光谱t…更多o氧化钛氧化钛光催化剂的粉末样品（Tio4，20 nm直径为20 nm）。他们成功地观察到了一个电子弛豫过程，该过程发生在1 ps之内，几十秒钟内的电孔重组过程以及从氧化钛到铂共催化剂的电子迁移过程以2 ps为单位。结果解释了当将铂共催化剂加载到氧化钛颗粒中时，催化活性增加的机制。3。对对称和不对称替代的双ththrylstime-bianthrylstime-bianthrylstime-the近弗拉德频谱的电荷转移状态的含量是对称和不对称的替代频谱。仅针对对称取代的双晶观察到近红外区域中的CT状态抽象带。对于不对称取代的双乙烯没有观察到它们。强烈建议在近红外区域观察到的CT抽象带表示两个蒽环之间的电荷共振相互作用。较少的