Center for Atomic-scale Materials Design, Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
Nano Lett. 2010 Oct 13;10(10):4260-5. doi: 10.1021/nl101688a.
Quantum interference (QI) of electron pathways has recently attracted increased interest as an enabling tool for single-molecule electronic devices. Although various molecular systems have been shown to exhibit QI effects and a number of methods have been proposed for its analysis, simple guidelines linking the molecular structure to QI effects in the phase-coherent transport regime have until now been lacking. In the present work we demonstrate that QI in aromatic molecules is intimately related to the topology of the molecule's π system and establish a simple graphical scheme to predict the existence of QI-induced transmission antiresonances. The generality of the scheme, which is exact for a certain class of tight-binding models, is proved by a comparison to first-principles transport calculations for 10 different configurations of anthraquinone as well as a set of cross-conjugated molecular wires.
量子干涉（QI）的电子途径最近引起了人们的兴趣，因为它是一种用于单分子电子设备的工具。虽然已经证明了各种分子系统具有 QI 效应，并且已经提出了许多用于分析 QI 的方法，但是将分子结构与相干传输状态下的 QI 效应联系起来的简单准则直到现在还没有。在本工作中，我们证明了芳香族分子中的 QI 与分子的π系统的拓扑结构密切相关，并建立了一个简单的图形方案来预测 QI 诱导的传输反共振的存在。该方案对于某些紧束缚模型是精确的，通过与蒽醌的 10 种不同构型以及一组交叉共轭分子线的第一性原理传输计算进行比较，证明了其通用性。
