...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Dalton transactions: An international journal of inorganic chemistry >Strong two-photon absorption and ultrafast dynamics of meso-functionalized 'push-pull' trans-A(2)BC porphyrins
【24h】

Strong two-photon absorption and ultrafast dynamics of meso-functionalized 'push-pull' trans-A(2)BC porphyrins

机译：Meso官能化“推拉”反式A（2）BC卟啉的强双光子吸收和超快动态

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A new series of "push-pull" meso-substituted trans-A(2)BC porphyrins, where A = mesityl, B = phenothiazine (push) and C = o/p-nitrophenyl moiety (pull) and M = 2H, Ni(ii), Cu(ii), and Zn(ii), were synthesized. These trans-A(2)BC porphyrins were characterized by various techniques viz. UV-Vis, fluorescence and NMR spectroscopy, matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, cyclic voltammetry, single-crystal X-ray diffraction analysis and density functional theory (DFT) studies. The single crystal structure of the newly synthesized free base trans-H(2)A(2)BC porphyrin (2) revealed the orientation of meso-substituents and the planar conformation of the porphyrin core. All newly synthesized free base trans-H(2)A(2)BC porphyrins (1 or 2) and their metal complexes exhibited a sharp Soret band. The first reduction potential of all synthesized trans-MA(2)BC porphyrins showed an anodic shift as compared with that of meso-tetraphenylporphyrins (MTPPs) due to the strong electron withdrawing nature of the nitrophenyl group. In general, the first oxidation potential of trans-MA(2)BC porphyrins shows a cathodic shift due to the electron donating phenothiazine moiety as compared to that of MTPPs. p-Nitrophenyl appended trans-A(2)BC porphyrins exhibited large ground state dipole moment values (8.59-9.64 D) as compared to MTPPs (0.0013-0.052 D) owing to the polarized "push-pull" effect of meso-substituents such as phenothiazine (push) and nitrophenyl (pull) moieties. Femtosecond nonlinear optical (NLO) studies performed with kHz pulses at 800 nm revealed strong two-photon absorption coefficients (similar to 0.082-0.0953 cm GW(-1)) and cross-sections (similar to 1.71-1.95 x 10(3) GM) for these "push-pull" porphyrins. We have also attempted to understand the NLO coefficients in terms of the structural changes in these porphyrin derivatives. A comparison that has been accomplished with similar porphyrin molecules and under similar experimental conditions revealed the superior performance of the title molecules. Furthermore, femtosecond transient absorption studies demonstrated several ultrafast processes from various excited states in these porphyrins, useful for identifying the processes relevant to optical switching applications.
机译：合成了一系列新的“推拉”介观取代反式-A（2）BC卟啉，其中A=均三甲苯，B=吩噻嗪（推），C=o/p-硝基苯基部分（拉），M=2H，Ni（ii），Cu（ii）和Zn（ii）。这些反式-A（2）BC卟啉通过各种技术进行表征，即。紫外可见光谱、荧光光谱和核磁共振光谱、基质辅助激光解吸电离飞行时间（MALDI-TOF）质谱、循环伏安法、单晶X射线衍射分析和密度泛函理论（DFT）研究。新合成的自由基反式-H（2）A（2）BC卟啉（2）的单晶结构揭示了介观取代基的取向和卟啉核的平面构象。所有新合成的自由基反式-H（2）A（2）BC卟啉（1或2）及其金属配合物均显示出尖锐的Soret带。由于硝基苯基的强吸电子性质，所有合成的反式MA（2）BC卟啉的第一还原电位与中间四苯基卟啉（MTPPs）相比显示出阳极位移。总的来说，与MTPPs相比，反式MA（2）BC卟啉的第一氧化电位由于给电子吩噻嗪部分而显示出阴极位移。由于吩噻嗪（push）和硝基苯基（pull）等中间取代基的极化“推拉”效应，与MTPPs（0.0013-0.052 D）相比，添加对硝基苯基的反式A（2）BC卟啉表现出较大的基态偶极矩值（8.59-9.64 D）。用800nm的kHz脉冲进行的飞秒非线性光学（NLO）研究显示，这些“推拉”卟啉具有很强的双光子吸收系数（类似于0.082-0.0953 cm GW（-1））和截面（类似于1.71-1.95 x 10（3）GM）。我们还试图通过这些卟啉衍生物的结构变化来理解NLO系数。在类似的实验条件下，与类似的卟啉分子进行了比较，结果表明，标题分子的性能优越。此外，飞秒瞬态吸收研究证明了这些卟啉中不同激发态的几个超快过程，有助于识别与光开关应用相关的过程。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号