Time-Resolved Resonance Raman Study of the Triplet State of the p-Hydroxyphenacyl Acetate Model Phototrigger Compound
Time-Resolved Resonance Raman Study of the Triplet State of the p-Hydroxyphenacyl Acetate Model Phototrigger Compound
复制标题
对羟基苯甲酰乙酸模型光触发化合物三重态的时间分辨共振拉曼研究
DOI：
10.1021/jp0376020
复制
发表时间：
2004
影响因子：
3.3
通讯作者：
D. Phillips
中科院分区：
文献类型：
--
作者：
Chensheng Ma;W. Chan;W. Kwok;P. Zuo;D. Phillips
利用皮秒和纳秒时间分辨共振拉曼光谱研究了光触发化合物对羟基苯甲酰甲基乙酸酯（HPA）在乙腈溶液中的动力学和结构。观察到一种中间体，其表现出明显的氧猝灭。该中间体被鉴定并归因于HPA的ππ* 三重态。在早期皮秒时间的时间演化表明快速的系间交叉转换和随后的松弛的多余能量的初始形成的三重态。用密度泛函理论（DFT）B3 LYP/6- 311 G ** 计算了HPA三重态和基态的结构和振动频率。实验和理论结果进行了比较和讨论的初始途径对羟基苯甲酰甲基脱保护反应和相对于其他芳香族羰基化合物的三重态的性质。目前的研究结果表明，应用超快振动的实用性…
Picosecond and nanosecond time-resolved resonance Raman spectroscopy have been used to study the dynamics and structure of the phototrigger compound p-hydroxyphenacyl acetate (HPA) in acetonitrile solution. An intermediate was observed that exhibited significant quenching by oxygen. This intermediate was identified and attributed to the ππ* triplet state of HPA. Temporal evolution at early picosecond times indicates rapid intersystem crossing conversion and subsequent relaxation of the excess energy of the initially formed triplet state. B3LYP/6-311G** density functional theory (DFT) calculations were done to determine the structures and vibrational frequencies for both the HPA triplet and ground states. The experimental and theoretical results were compared and discussed in relation to the initial pathway for the p-hydroxyphenacyl deprotection reaction and the nature of the triplet state relative to other aromatic carbonyl compounds. The present results demonstrate the utility of applying ultrafast vibra...