The Structure and Reactions of Large Clusters Studies by The Rotational Coherence Method

了解溶剂化簇合物的结构对于在微观水平上理解其分子内反应是至关重要的。然而，像溶剂化簇这样的大分子的光谱测定的困难使我们无法将溶剂化簇的分子内反应与它们的结构联系起来。分子越大，传统的高分辨率频率光谱法确定分子结构的优势就越小。溶剂分子的数目和位置如何影响分子内电荷转移反应的速率是我们的主要兴趣。我们采用旋转相干光谱作为工具来确定这种团簇的结构，联蒽与其他溶剂分子形成的络合物具有比单体低的对称性。此外，分子内电荷转移反应涉及导致主轴旋转的大的结构变化。这些事实阻止了用时间相关的单光子观测旋转相干信号 ...更多信息 吨计数法，测量电子激发态的转动能级结构。因此，泵浦-探测方法被用来获得电子基态的水配合物的结构信息，这表明通过光激发的电荷转移态的非绝热转变。经过对短脉冲激光放大系统稳定性的努力，我们最终用这种方法观测到了水络合物的转动相干信号。电子激发态的旋转相干信号的损失和电子基态的旋转相干的观察表明分子内电荷转移后的大的结构变化。为了进行这项研究，Kajimoto教授访问了牛津大学，Langford博士访问了京都。此外，还研究了其他即使不与极性溶剂分子成簇也能发生分子内电荷转移反应的分子，即4-（N，N-二甲氨基）乙基苯甲酸酯（牛津大学）和4-（N，N-二甲氨基）-3，5-二甲基苄腈（京都）。通过对它们结构的分析，建立了扭转势与电荷转移反应形成的密切关系。为了进行这项研究，西蒙斯教授访问了京都，李女士访问了牛津。少

Knowledge of structure of solvated cluster is essentially important to understand its intramolecular reaction in microscopic level. However, the difficulty of spectroscopic determination of big molecules like solvated clusters prevents us from relating intramolecular reactions of solvated clusters with their structure. The bigger a molecule is, the less advantageous is traditional high-resolution frequency spectroscopy to determine molecular structure. How the number and location of solvent molecules affect the rate of intramolecular charge transfer reaction is our main interest. We adopted rotational coherence spectroscopy as a tool to determine the structure of such clusters.Complexes between bianthryl and other solvent molecules have lower symmetry than the monomer. In addition, intramolecular charge transfer reaction involves large structural change causing the rotation of the principal axis. These facts prevent observing rotational coherence signals with time-correlated single-pho … More ton counting method, which measures the rotational level structure of electronically excited state. Therefore, the pump-probe method was applied to obtain structural information of evectronically ground state of water complex, which shows non-adiabatic transition to a charge transfer state via photoexcitation. After some efforts to obtain good stability of the amplification system of short pulse laser, we finally observed the rotational coherence signal of water complex with this method. Loss of the rotational coherence signal in electronically excited state and observation of the rotational coherence in the electronically ground state suggest a large structural change following intramolecular charge transfer. To perform this research, Prof.Kajimoto visited Oxford and Dr.Langford visited Kyoto.Other molecules cousing intramolecular charge transfer reaction even without clustering with polar solvent molecules, 4- (N,N-dimethylamino) ethylbenzoate (Oxford) and 4- (N,N-dimethylamino) -3,5-dimethylbenzonitrile (Kyoto) were also investigated. From the analysis of their structure, close relation between torsional potential and formation of charge transfer reaction is established. To perform this research, Prof.Simons visited Kyoto and Ms.Lee visited Oxford. Less