论文标题
对三核金属弦复合物的热电学行为的理论洞察力，该复合物与金纳米电极相连：一项第一原理研究
Theoretical insight into the thermoelectric behavior of tri-nuclear metal-string complexes laced with gold nanoelectrodes: A first-principles study
论文作者
论文摘要
准-1D框架中的金属弦复合物不仅可以用作纳米级互连，而且作为纳米电子设备的主动功能元件，在分子电子中可能起重要作用。但是，由于此类纳米缝合的潜在体积热量产生，电路稳定性通常成为主要问题，这有必要研究分子尺度上的热传输性能。在这里，我们报告了各种三核金属弦复合物的热电行为，$ [m-m-m]（dpa）_4（ncs）_2 $ for $ m \ in \ in \ {cr，ru \} $，桥接Au（111）纳米线作为纳米电极。基于我们从\ textit {First-principles}的电荷传输分析，我们发现，由于$π^{*} $ obitals的耦合，主要是由于$π^{*} $ frou frou and ru and $σ_{nb} $ nb} $ nb}。这种类型的金属弦连接连接也可以表现出较强的库仑相互作用，因此其热电行为开始偏离Wiedemann-Franz定律。 Our results further suggest that metal-string complexes can render better thermoelectric devices especially at the molecular-scale with the thermopower as high as 172 $μV/K$ at 300 K. Considering the contributions from both electrons and phonons, even a high \textit{figure of merit} of $ZT \sim 2$ may be attained for Cr-Cr-Cr based metal-string molecular junctions at room temperature.热电效率的共振增强似乎通过改变点间静电相互作用而发生在此类系统中，可以通过将Cr和Ru原子掺入此类三核金属弦乐配合物中来控制。
Metal-string complexes in the quasi-1D framework may play an important role in molecular electronics by serving not only as nanoscale interconnects but also as active functional elements for nanoelectronic devices. However, because of the potential volumetric heat generation across such nanojunctions, the circuit stability becomes often a major concern, which necessitates to study the heat transport properties at the molecular-scale. Here we report the thermoelectric behavior of various tr-nuclear metal-string complexes, $[M-M-M](dpa)_4(NCS)_2$ for $M \in \{Cr,Ru\}$, bridging Au(111) nanowires as nanoelectrodes. Based on our charge transport analysis from \textit{first-principles}, we find that the dominant transmission peaks tend to move away from the Fermi level upon systematic rutheniation in chromium-based metal-string complexes due mainly to the coupling of $π^{*}$ orbitals from Ru and $σ_{nb}$ orbitals from Cr. Such type of a metal-string junction can also exhibit strong Coulomb interaction so that its thermoelectric behavior begins to deviate from the Wiedemann-Franz law. Our results further suggest that metal-string complexes can render better thermoelectric devices especially at the molecular-scale with the thermopower as high as 172 $μV/K$ at 300 K. Considering the contributions from both electrons and phonons, even a high \textit{figure of merit} of $ZT \sim 2$ may be attained for Cr-Cr-Cr based metal-string molecular junctions at room temperature. Resonant enhancement in the thermoelectric efficiency appears to occur in such systems through alteration of inter-dot electrostatic interactions, which can be controlled by incorporating Cr and Ru atoms in such tri-nuclear metal-string complexes.
