State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian, China.
J Comput Chem. 2011 Nov 30;32(15):3218-25. doi: 10.1002/jcc.21904. Epub 2011 Aug 11.
Attaching electron-withdrawing substituent to organic conjugated molecules is considered as an effective method to produce n-type and ambipolar transport materials. In this work, we use density functional theory calculations to investigate the electron and hole transport properties of pentacene (PENT) derivatives after substituent and simulate the angular resolution anisotropic mobility for both electron and hole transport. Our results show that adding electron-withdrawing substituents can lower the energy level of lowest unoccupied molecular orbital (LUMO) and increase electron affinity, which are beneficial to the electron injection and ambient stability of the material. Also the LUMO electronic couplings for electron transport in these pentacene derivatives can achieve up to a hundred meV which promises good electron transport mobility, although adding electron-withdrawing groups will introduce the increase of electron transfer reorganization energy. The final results of our angular resolution anisotropic mobility simulations show that the electron mobility of these pentacene derivatives can get to several cm(2) V(-1) s(-1), but it is important to control the orientation of the organic material relative to the device channel to obtain the highest electron mobility. Our investigation provide detailed information to assist in the design of n-type and ambipolar organic electronic materials with high mobility performance.
将吸电子取代基附着到有机共轭分子上被认为是产生 n 型和双极输运材料的有效方法。在这项工作中，我们使用密度泛函理论计算来研究取代基后并五苯（PENT）衍生物的电子和空穴输运性质，并模拟电子和空穴输运的各向异性迁移率。我们的结果表明，添加吸电子取代基可以降低最低未占据分子轨道（LUMO）的能级并增加电子亲和力，这有利于材料的电子注入和环境稳定性。此外，这些并五苯衍生物中电子输运的 LUMO 电子耦合可以达到数百毫电子伏特，这有望实现良好的电子输运迁移率，尽管添加吸电子基团会引入电子转移重组能的增加。我们的各向异性迁移率模拟的最终结果表明，这些并五苯衍生物的电子迁移率可以达到几厘米 2 V（-1） s（-1），但控制有机材料相对于器件沟道的取向以获得最高的电子迁移率是很重要的。我们的研究提供了详细的信息，以协助设计具有高迁移率性能的 n 型和双极有机电子材料。
