Supramolecular interaction-induced self-assembly of organic molecules into ultra-long tubular crystals with wave guiding and amplified spontaneous emission
作者:Yuanxiang Xu、Houyu Zhang、Feng Li、Fangzhong Shen、Huan Wang、Xianjie Li、Yang Yu、Yuguang Ma
DOI:10.1039/c1jm14815j
日期:——
Ultra-long tubular crystals (length up to 10 mm and diameter of 70 μm) of a small organic functional molecule, 1,4-bis(2-cyano-2-phenylethenyl)benzene (BCPEB), are successfully prepared through a physical vapor transport (PVT) method. On the basis of crystal structural analysis and density functional theory calculations, we show that the formation of such tubular crystals is drawn by the branched hydrogen bonds between the BCPEB molecules. High crystalline quality, highly ordered molecular orientation, and hollow-like topological structure enable the crystal to exhibit optical wave guided emission behaviors with low optical loss (3 dB mm−1) and highly polarized emission (the polarized ratio is about 20). Amplified spontaneous emission (ASE) characteristics of the tubular crystals were also studied; the net gain coefficients at the peak wavelength and the threshold are 91.7 cm−1 and 36 kW cm−2, respectively.
通过物理气相法成功制备了有机小分子1,4-双(2-氰基-2-苯基乙烯基)苯(BCPEB)的超长管状晶体(长度可达10毫米,直径为70微米)运输(PVT)方法。在晶体结构分析和密度泛函理论计算的基础上,我们表明这种管状晶体的形成是由BCPEB分子之间的支化氢键引起的。高结晶质量、高度有序的分子取向和中空拓扑结构使晶体表现出低光损耗(3 dB mm−1)和高偏振发射(偏振比约为20)的光波导发射行为。还研究了管状晶体的放大自发发射(ASE)特性;峰值波长和阈值处的净增益系数分别为 91.7 cm−1 和 36 kW cm−2。