Alkanedithiol 單分子接面系統的熱電性質

Thermoelectric properties of Alkanedithiol single-molecule junctions

謝孟諺(MENG-YEN HSIEH)

指導教授 ： 陳煜璋

國立交通大學/理學院/電子物理系所/碩士(2019年)

摘要

Alkanethiol 吸附在金屬表面(1 1 1)之穩定的結構，有幾種可能的方式。連接方式的不同最直接的影響就是電子的傳輸性質會有所不同。我採用S吸附在金電極(1 1 1)有以下兩種。一種是 S-C鍵垂直的吸附在金電擊的Fcc site。另一種是S-C鍵與金電擊(1 1 1)的法向量有個夾角且吸附在靠近金電擊的Fcc bridge。我們以第一原理方法計算n-alkanethiols (n = 2,4) 連接金電擊的電子傳輸性質。首先利用VASP計算出最穩定能量的電子結構，以DFT結合Lippmann-Schwinger equation 散射理論的架構下算出在不同偏壓下散射電子的非平衡態波函數。最後探討在不同的連接方式以及不同的碳顆數下，對Seebeck係數造成的影響以及熱電性質。

關鍵字

熱電性質

並列摘要

In this thesis, the SAM structures for alkanethiols with short chains were studied on unreconstructed Au (1 1 1) surfaces. There are several possible positions for S adsorbed on Au (1 1 1). I adopt the Fcc site with the S–C bond perpendicular to the Au (1 1 1) surface.Also, I adopt the Fcc bridge with the S–C is inclined by 〖22〗^。for another system.
under the framework of the density functional theory and the Lippmann-Schwinger equation ,we report DFT calculations for density of states、 Seebeck coefficient and thermoelectric properties of Alkanedithiol.

並列關鍵字

Alkanedithiol

參考文獻

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