TWO-PHOTON STUDIES OF AMINO ACIDS AND NUCLEIC ACIDS

提供选择规则的双光子电子态谱 补充那些普通的紫外-可见光谱是用来研究 芳香族氨基酸的低位电子单重激发态， DNA碱基、核苷酸和DNA聚合物。 模型芳烃体系的研究 为了建立一座牢固的理解桥梁， 取代的芳香族化合物和不太了解的吲哚、嘌呤 和嘧啶碱基。 INDO/S计算，重点是彻底 将应用基组、参数和几何效应调查 每个实验。 长期目标是实现坚实的基础 借助跃迁密度图， 这些系统的电子结构--一个享有类似程度的 对简单取代苯的信任。 一些重点是在 定位色氨酸发色团中的“La起源”的特定目的， 吲哚;单光子激光紫外偏振荧光实验 在蒸气和碳氢化合物玻璃中提出支持平行双光子 实验 单光子荧光和双光子荧光实验 单股和双股病毒DNA的建议，特别是看看， 内源荧光依赖于超螺旋和蛋白质复合。 观察Z-DNA的固有荧光。

Two-photon electronic state spectroscopy which offers selection rules complementary to those of ordinary UV-visible spectroscopy is used to study the low lying electronic singlet excited states of aromatic amino acids, DNA bases, nucleotides and DNA polymers. Studies of model aromatic systems are continued for the purpose of forming a firm bridge of understanding between substituted aromatics and the less well-understood indoles, purines and pyrimidine bases. INDO/S calculations, with emphasis on thorough investigation of basis set, parameter and geometry effects, will be applied to each experiment. The long range goal is to attain a firmly based understanding, with the aid of transition density pictures, of the electronic structure of these systems -- one that enjoys a similar degree of trust given to simple substituted benzenes. Some focus is on the specific aim of locating the "La origin" in the tryptophan chromaphore, indole; one-photon laser UV polarized fluorescence experiments on indoles in vapor and hydrocarbon glass are proposed to support parallel two-photon experiments. One-photon fluorescence as well as two-photon experiments on one and two-stranded viral DNA's are proposed, especially to see if intrinsic fluorescence depends on supercoiling and protein complexation. The intrinsic fluorescence of Z-DNA will be observed.