Influence of vibrations on electron transport through nanoscale contacts
Influence of vibrations on electron transport through nanoscale contacts
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DOI：
10.1002/pssb.201350212
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发表时间：
2013-11-01
影响因子：
1.6
通讯作者：
Pauly, Fabian
中科院分区：
文献类型：
--
作者：
Buerkle, Marius;Viljas, Janne K.;Pauly, Fabian
在本文中，我们提出了一种新的半解析方法来计算一阶电子振动（EV）耦合常数的密度泛函理论的框架内。它结合了解析表达式的一阶导数的Kohn-Sham算子相对于核位移与耦合微扰Kohn-Sham理论，以确定电子密度矩阵的导数。这使我们能够有效地计算准确的EV耦合常数。我们应用我们的方法来描述金属和分子结的非弹性电子隧穿（IET）谱。一个金结桥接的原子链被用来验证开发的方法，再现既定的实验和理论结果。对于辛二硫醇和辛二胺单分子结，我们讨论了锚定基团和机械拉伸对IET谱的影响。
In this paper, we present a novel semi-analytical approach to calculate first-order electron-vibration (EV) coupling constants within the framework of density functional theory. It combines analytical expressions for the first-order derivative of the Kohn-Sham operator with respect to nuclear displacements with coupled-perturbed Kohn-Sham theory to determine the derivative of the electronic density matrix. This allows us to efficiently compute accurate EV coupling constants.We apply our approach to describe inelastic electron tunneling (IET) spectra of metallic and molecular junctions. A gold junction bridged by an atomic chain is used to validate the developed method, reproducing established experimental and theoretical results. For octanedithiol and octanediamine single-molecule junctions, we discuss the influence of the anchoring group and mechanical stretching on the IET spectra.