Inelastic Electron Tunneling of C60 on Gold Surfaces from First-Principles Calculations

详细信息    查看全文

• 作者：Audrey S茅gerie ; Vincent Li茅geois ; Beno卯t Champagne
• 刊名：Journal of Physical Chemistry C
• 出版年：2015
• 出版时间：January 8, 2015
• 年：2015
• 卷：119
• 期：1
• 页码：803-818
• 全文大小：1119K
• ISSN：1932-7455

文摘

The simulation of IET spectra of a single C₆₀ molecule placed between two gold electrodes has evidenced the high sensitivity of IET spectroscopy to the C₆₀ orientation and also to the molecule鈥揺lectrode distance. When considering a small molecule鈥揺lectrode distance (d = 2.0 脜) the dominant peaks are associated with longitudinal displacements of the contact moieties. For d = 2.8 脜, depending on the adsorption configuration the dominant signatures are not associated with the same atomic motions, while for larger distances (d = 4.0 脜) the four configurations only exhibit peaks corresponding to C鈥揅 stretching modes. The best agreement between experimental measurements and our theoretical calculations has been found when considering a molecular junction characterized by two hexagons of the C₆₀ molecule aligned parallel to the Au(111) surfaces and centered on a hcp site, with a distance between the center of the hexagon aligned parallel to the Au(111) surface and the hcp site of the source (drain) reservoir of 2.8 脜 (3.4 脜). Our approach can therefore be of great help in understanding, beside the intrinsic vibrational behavior of one compound, the small structural variations induced by the proximity to the metal electrodes.