Tailored polymer materials exhibiting high-glass transition temperatures, cross-linked matrices, and/or strong intermolecular interactions containing electric-field poled nonlinear optical (NLO) chromophores are promising materials for applications in optical telecommunication, high-performance computing, and data transmission. Although the current design parameters have led to significant advances in NLO materials, we introduce an alternative, yet highly effective, approach in which a NLO chromophore is cocrystallized with a polymer, forming a noncentrosymmetric hybrid host–guest complex. Specifically, poly(ethylene oxide) (PEO) and 2-chloro-4-nitroaniline (CNA) will cocrystallize and exhibit second harmonic generation (SHG) activity due to the formation of a noncentrosymmetric cocrystalline unit cell where the chromophore exhibits acentric alignment. Furthermore, the hybrid PEO/CNA films exhibit interesting SHG activity at elevated temperature in which SHG intensity decreases to zero when the cocrystal orientation randomizes due to sample melting. Aligning and maintaining a cocrystalline domain orientation via the formation of hybrid host–guest complexes, while imparting SHG properties, is an innovative approach for creating materials exhibiting SHG properties.

中文翻译：

---

具有二阶非线性光学特性的共晶聚合物薄膜

具有高玻璃化转变温度、交联基质和/或包含电场极化非线性光学 (NLO) 发色团的强分子间相互作用的定制聚合物材料是用于光通信、高性能计算和数据传输的有前途的材料。尽管当前的设计参数已导致 NLO 材料取得重大进展，但我们引入了一种替代但高效的方法，其中 NLO 发色团与聚合物共结晶，形成非中心对称的混合主客体复合物。具体来说，聚(环氧乙烷) (PEO) 和 2-氯-4-硝基苯胺 (CNA) 将共结晶并表现出二次谐波产生 (SHG) 活性，这是由于形成了发色团呈现偏心排列的非中心对称共晶晶胞。此外，混合 PEO/CNA 薄膜在高温下表现出有趣的 SHG 活性，其中当共晶取向由于样品熔化而随机化时，SHG 强度降低至零。通过形成混合主客体复合物来对齐和保持共晶畴取向，同时赋予 SHG 特性，是一种创造具有 SHG 特性的材料的创新方法。混合 PEO/CNA 薄膜在高温下表现出有趣的 SHG 活性，其中当共晶取向由于样品熔化而随机化时，SHG 强度降低至零。通过形成混合主客体复合物来对齐和保持共晶畴取向，同时赋予 SHG 特性，是一种创造具有 SHG 特性的材料的创新方法。混合 PEO/CNA 薄膜在高温下表现出有趣的 SHG 活性，其中当共晶取向由于样品熔化而随机化时，SHG 强度降低至零。通过形成混合主客体复合物来对齐和保持共晶畴取向，同时赋予 SHG 特性，是一种创造具有 SHG 特性的材料的创新方法。