作　　者： (王串串）; (朱春梅）; (苏梦笛）; (陈宇飞）; (赵蔡斌）;

机构地区： 陕西理工大学化学与环境科学学院,陕西汉中723000

出　　处： 《分子科学学报》 2017年第4期265-275,共11页

摘　　要： 采用密度泛函理论(DFT)方法结合不相干的电荷跳跃模型和随机Monte Carlo模拟,研究了2种四噻吩并萘晶体(AT1和AT2)的分子结构、电子性质及电荷载流子传输参数,并预测了这2种晶体室温下空穴和电子迁移率的各向异性.结果表明标题化合物具有近似平面的刚性骨架结构,电荷传输过程中分子的结构弛豫相当小.基于绝热势能面法计算的AT1和AT2分子空穴/电子传输内重组能分别为9.300×10^(-2)/1.100×10^(-1)eV和1.020×10^(-1)/1.290×10^(-1) eV,外重组能分别为1.835×10^(-2)/1.711×10^(-2) eV和1.857×10^(-2)/1.747×10^(-2) eV.利用Monte Carlo随机模拟方法预测的2种分子晶体室温(300K)下空穴/电子迁移率平均值分别为4.976×10^(-3)/2.766×10^(-2) cm^2 V^(-1)s^(-1)和3.857×10^(-3)/1.478×10^(-2)cm^2 V^(-1)s^(-1).此外,迁移率的角度依赖性研究表明2种载流子在AT1和AT2晶体aob平面传输时表现出显著的各向异性,其最大值均沿着电荷传输积分最大的方向,为制备高性能场效应晶体管器件提供了参考. In the current work,the charge transport properties of two tetrathienoanthracenenes,anthra[2.1-b：3,4-b′：6,5-b″：7,8-b]terathiophene（AT1）and anthra[1.2-b：4,3-b′：5,6-b″：8,7-b]terathiophene（AT2）,have been studied theoretically by means of density functional theory（DFT）calculations coupled with the incoherent charge-hopping model and random Monte Carlo simulation.The results show that the AT1 and AT2possess an excellent planar configuration,and the structural relaxation in the charge transfer process is very small.Based on the adiabatic potential energy surface method,the internal reorganization energy in hole and electron transfers are estimated to be 9.300×10^（-2）/1.100×10^（-1） eV for AT1 molecule,which slightly increase to 1.020×10-1/1.29×10^（-1） eV for AT2.Relatively,the external reorganization energy is predicted to be as small as 1.835×10^（-2）/1.711×10-2eV and1.857×10^（-2）/1.747×10^（-2） eV in hole and electron transfers for two molecules.In addition,the 3D-averaged hole and electron mobility at room temperature are predicted to be 4.967×10-3 and 2.766×10-2 cm2 V^（-1）s^（-1） for AT1 crystal,which are 3.857×10-3 and 1.478×10-2 cm2 V^（-1）s^（-1） for AT2 crystal.Moreover,the simulation of angle-dependence mobility shows that both charge carriers exhibit remarkably anisotropic transport in the aob plane of AT1 and AT2crystals,and the maximum mobility is found to be along the intermolecularπ-πinteraction direction.In brief,this investigation can provided some valuable references for the fabrication of high-performance OFET devices.

关 键 词： 密度泛函理论 四噻吩并萘 电荷传输 各向异性