两种新型芴类衍生物的三光子吸收特性研究

摘要

In order to study effect of molecular structure on three-photon absorption(3PA) characteristics, two novel fluorene-based derivatives:2, 7-bis(2-(4-methoxyphenyl)ethynyl)-9,9-dioctyl-9H-fluorene(A) and 2-bromo-7-(2-(4-methoxyphenyl)ethynyl)-9,9-dioctyl-9H-fluorene(B) were synthesized.The 3PA cross-sections of both the compounds were tested by using a Q-switched Nd∶YAG laser at 1064nm.The 3PA cross-sections were obtained , i.e., (6.03 ±0.6) × 10-76 cm6 · s2/photon2 and (4.25 ±0.4) ×10 -76 cm6 · s2/photon2 respectively.The geometries in the ground states and electronic structures of both the compounds were investigated by density functional theory methods and time -dependent density functional theory methods of Gaussian 03, and the impact on the three-photon absorption characteristics was analyzed.%为了研究分子结构对三光子吸收的影响，合成了两种新型芴类衍生物，分别是2，7-二（2-4（甲氧基苯基）乙炔基）-9，9-二辛基-9H-芴（A）和2-溴-7-（2-（4-甲氧基苯基）乙炔基）-9，9-二辛基-9H-芴（B），采用1064nm的Nd∶YAG激光器测试其三光子吸收截面的方法，得到了它们的三光子吸收截面分别高达（6．03±0．6）×10-76 cm6· s2/photon2和（4．25±0．4）×10-76 cm6· s2/photon2的结果，在高斯03软件下，用密度泛函方法对这两个分子进行了结构优化，并用含时密度泛函理论计算了它们的激发态能量和电子轨道。结果表明，分子内电荷转移方向对三光子吸收存在影响。