Chen Renai, Sharony Inon, Nitzan Abraham
Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel.
J Phys Chem Lett. 2020 Jun 4;11(11):4261-4268. doi: 10.1021/acs.jpclett.0c00471. Epub 2020 May 13.
We consider interference effects in vibrational heat conduction across single-molecule junctions. Previous theoretical descriptions of such effects have relied on the quantum Landauer-type expression for heat transport by harmonic molecules, and such observations are sometimes termed "quantum interference". Here we demonstrate via classical atomistic simulations of heat conduction in benzenedithiol single-molecule junctions that the room-temperature effect is essentially classical. In fact, classical simulations and quantum evaluation of room-temperature heat conduction in these systems yield similar results. Simulations of para-, meta-, and ortho-connected benzenedithiols between gold substrates yield conductions in the order para > ortho > meta, which is similar to trends found in the electronic conduction of these structures. The (essentially classical) interference origin of this ordering is indicated by the similarity of the quantum and classical behaviors of these systems.
我们研究了单分子结中振动热传导的干涉效应。此前对这类效应的理论描述依赖于通过谐波分子进行热传输的量子朗道尔型表达式，这类观测有时被称为“量子干涉”。在这里，我们通过对苯二硫醇单分子结热传导的经典原子模拟表明，室温效应本质上是经典的。事实上，这些系统在室温下热传导的经典模拟和量子评估产生了相似的结果。在金基底之间对对位、间位和邻位连接的苯二硫醇进行模拟，得到的热导率顺序为对位 > 邻位 > 间位，这与这些结构的电子传导中发现的趋势相似。这些系统量子行为和经典行为的相似性表明了这种排序（本质上是经典的）干涉起源。
