Synthesis of Polymers and Oligomers for Nonlinear Optical Activity

通过优化电子离域和分子内 电荷转移，聚合物产生三阶非线性光学 已经制备了超过10-9 esu的结晶度， 薄膜（1微米）。 品质因数高达104， 获得的原始材料。 掺杂（分子间电荷 转移）在某些情况下产生甚至更大的值。 梯子和 在初步研究中制备的苯基多烯材料还 表现出掺杂诱导的视觉透明度，即，漂白 π-π * 带间跃迁和伴随的 带内（极化子/双极化子）跃迁。 给电子和 观察到撤回取代基稳定这些中间间隙 国家物种。 离域π电子系统的反应性 与分子氧的影响进行了研究， 非线性光学中电子离域中断 活动得到了证实。 这项研究的重点是 聚合物、共聚物和复合材料的进一步发展 用于增强非线性光学活性的材料。 特别 注意力集中在空气稳定材料的开发上， 模型化合物（低聚物）获得的数据的相关性 和聚合物。 线性和非线性的共聚物和复合材料 将开发光学材料。 组件将如此 选择折射率在弱光下匹配 强度，但在高强度下不匹配。

By optimizing electron delocalization and intramolecular charge transfer, polymers yielding third order nonlinear optical susceptibilities in excess of 10-9 esu have been prepared as thin (1 micron) films. Figures of merit as high as 104 have been obtained for pristine materials. Doping (intermolecular charge transfer) yields even larger values in some cases. Ladder and penylpolyene materials prepared in preliminary studies also exhibit doping-induced visual transparency, i.e., bleaching of the pi-pi* interband transition and accompanying appearance of intraband (polaron/bipolaron) transitions. Electron-donating and withdrawing substituents are observed to stabilize these mid-gap state species. The reactivity of delocalized pi electron systems with molecular oxygen has been investigated and the effect of interruption of electron delocalization upon nonlinear optical activity has been demonstrated. This research focues upon further development of polymers, copolyers, and composite materials for enhanced nonlinear optical activity. Particular attention is paid to the development of air-stable materials and to correlation of data obtained for model compounds (oligomers) and polymers. Copolymers and composites of linear and nonlinear optical materials will be developed. Components will be so chosen that indices of refraction are matched at low light intensities but are mismatched at high intensities.