量化方法研究分子结BEMP和TEMP的电子输运特性

通过结合杂化密度泛函和前线轨道理论与弹性散射格林函数方法研究了BE- MP(benzene-1,4-di-ethynyl-4-mercaptophenyl)和TEMP(thiophene-2,5-di-ethynyl-4- mercaptophenyl)两分子结的输运性质。基于杂化密度泛函方法计算两扩展分子电子结构的基础上,计算了两分子的输运性质．计算结果显示:电流增加来源于电极和分子轨道的共振;电导曲线呈现出平台特征．在此基础上从扩展分子A(Au-BEMP-Au)中间的苯环的旋转而引起电流减小的角度解释了负微分电阻现象．

Quantum chemical investigations on the electron transport characteristics of BEMP and TEMP

By applying the hybrid density functional theory in coupled with elastic scattering Green's function method, we have investigated the transport characteristics of the molecular junctions composed of gold-BEMP-gold(benzene-l,4-di-ethynyl-4-mercaptophenyl)and gold-TEMP-gold (thiophene-2,5-di-ethynyl-4~mercapto-phenyl). According to the electronic structure of above extended molecule on the level of hybrid density functional theory, we further investigate the transport properties. The results show that the increase of current derive from the resonant between electrodes and molecule obitals, the curve of conductance exhibit flat step like characteristics. We also shed light on the negative differential resistance in terms of a twisting of the central ring induced by an applied potential.