POLYEN PHOTOPHYSICS--RESONANCE RAMAN INTENSITY STUDIES

紫外共振拉曼光谱，激发曲线， 绝对横截面将被测量为1，3-丁二烯，反式- 蒸汽和溶液中的1，3，5-己三烯和反式-1，3-戊二烯 阶段。气相共振拉曼和吸收光谱 将被分析以绘制出激发态势面 对于这些聚合物，特别是关于平面外， 扭曲 绝对横截面将允许定量 垂直激发电子态衰减的速率， 而扭转模式中的拉曼强度将揭示 对这个速率的贡献来自于双键的扭曲。 扩展到解决方案阶段将量化的影响， 激发态势能面上的环境， 这些多烯的非辐射衰变率以及 电子吸收光谱的不均匀加宽。 这些小的聚合物是最简单的模型系统， 生物学上重要的多烯醛，视网膜。 准确 激发态势能面的知识， 物理学，无论是在孤立的分子和溶液中， 对于发展描述顺式-反式的理论 含视色素的视黄质的光异构化， 细菌视紫红质

Ultraviolet resonance Raman spectra, excitation profiles, and absolute cross sections will be measured for 1,3-butadiene, trans- 1,3,5-hexatriene, and trans-1,3-pentadiene in vapor and solution phases. The vapor phase resonance Raman and absorption spectra will be analyzed to map out the excited state potential surfaces for these polyeners, particularly with regard to out of plane distortions. The absolute cross sections will permit quantitation of the rate at which the verticall excited electronic state decays, while the Raman intensities in torsional modes will reveal the contribution to this rate from twisting around double bonds. Extension to the solution phase will quantitate the effect of an environment on the excited state potential surfaces and nonradiative decay rates in these polyenes as well as the amount of inhomogeneous broadening of the electronic absorption spectra. These small polyeners are the simplest model systems for the biologically important polyene aldehyde, retinal. Accurate knowledge of their excited state potential surfaces and photophysics, both in the isolated molecules and in solution is important for developing theories to describe cis-trans photoisomerization of the retinal-containing visual pigments and bacteriorhodopsin.