Nozaki Daijiro, Schmidt Wolf Gero
Lehrstuhl für Theoretische Materialphysik, Universität Paderborn, Warburger Str. 100, Paderborn, 33098, Germany.
J Comput Chem. 2017 Jul 15;38(19):1685-1692. doi: 10.1002/jcc.24812. Epub 2017 May 7.
The current density in molecular wires connected to contacts is investigated within the nonequilibrium Green's function formalism combined with the Landauer approach. Energy-dependent and total current density through a series of molecular junctions are calculated in real space representation. A rich variety of current patterns including pronounced ring currents ("vortices") are found even in the defect-free minimal building blocks of molecular devices. The influences of contact positions, functional groups as well as atomic defects on the transport properties are examined systematically for prototypical ortho-, meta-, and para-substituted benzenes as well as heteroaromatic systems. It is found that substitutional functional groups mainly shift the molecular levels and retain characteristic transport channels, while a significant change of electronic pathways and conductance is induced by hetero-aromaticity. The current distribution is used to calculate the static magnetic field distribution in the carbon-based conductors. © 2017 Wiley Periodicals, Inc.
在非平衡格林函数形式体系与朗道尔方法相结合的框架下，对连接到触点的分子导线中的电流密度进行了研究。通过实空间表示法计算了通过一系列分子结的能量相关电流密度和总电流密度。即使在分子器件无缺陷的最小结构单元中，也发现了丰富多样的电流模式，包括明显的环形电流（“涡旋”）。对于典型的邻位、间位和对位取代苯以及杂芳族体系，系统地研究了接触位置、官能团以及原子缺陷对输运性质的影响。研究发现，取代官能团主要使分子能级发生移动并保留特征输运通道，而异芳族性则会引起电子路径和电导率的显著变化。利用电流分布来计算碳基导体中的静磁场分布。© 2017威利期刊公司
