School of Physics, Shandong University, Jinan 250100, China.
J Am Chem Soc. 2009 Nov 18;131(45):16418-22. doi: 10.1021/ja902573e.
We present a theoretical study of the elongation process of molecular junctions formed by octanedithiol molecule and Au electrodes. Five types of junctions that have different molecule-electrode coupling geometries are considered. It is found that the behavior of the H atom in the -SH group plays a crucial role in the system structure variation. The variation of the total energy and the average force needed to break the molecular junction are calculated, and each type of molecular junctions is found to have a characteristic breaking force. Comparing our theoretical results with those from experiment shows that the most probable coupling geometry was neglected in almost all the previous work. A dynamic analysis of the electronic structure of the molecular junctions is used to understand the variation of the system configuration.
我们对由十八硫醇分子和金电极形成的分子结的伸长过程进行了理论研究。考虑了具有不同分子-电极耦合几何形状的五种类型的结。结果发现，-SH 基团中的 H 原子的行为在系统结构变化中起着至关重要的作用。计算了总能量的变化和断开分子结所需的平均力，发现每种类型的分子结都具有特征的断裂力。将我们的理论结果与实验结果进行比较表明，在几乎所有以前的工作中都忽略了最可能的耦合几何形状。对分子结电子结构的动态分析用于理解系统构型的变化。
