Electronic structure of [121]tetramantane-6-thiol on gold and silver surfaces.
Electronic structure of [121]tetramantane-6-thiol on gold and silver surfaces.
复制标题
金和银表面上[121]四金刚烷-6-硫醇的电子结构。
作者：
Wenhua Zhang;B. Gao;Jinlong Yang;Ziyu Wu;Vincenzo Carravetta;Yi Luo
用密度泛函理论计算研究了[121]四金刚烷及其功能化化合物[121]四金刚烷-6-硫醇在不同贵金属表面上的电子光发射机理。发现分子与金属表面良好的化学键合是产生电子光发射的有利条件，但不是必要条件。分子和金属之间较低的功函数和较弱的杂化可以导致更有效的电子光电发射。结果表明，在忽略末态效应的情况下，简单的基态图像不能导致所研究体系的负电子亲和势。计算表明，通过激发最低未占据分子轨道中的电子，分子的最高单占据分子轨道可以移动到真空能级以上，导致负电子亲和力和累积电子的发射。
The mechanism for electron photoemission of [121]tetramantane and its functionalized compound [121]tetramantane-6-thiol adsorbed on different noble metal surfaces has been investigated by density functional theory calculations. It is found that good chemical bonding between molecules and metal surfaces is a helpful but not a necessary condition for electron photoemission. A lower work function and weaker hybridization between the molecule and the metal could lead to much more efficient electron photoemission. It is observed that, neglecting final state effect, a simple ground state picture cannot result in negative electron affinity for the systems under investigation. Calculations have shown that by exciting an electron in the lowest unoccupied molecular orbital, the highest singly occupied molecular orbital of the molecule can be shifted above the vacuum level, resulting in negative electron affinity and emission of the accumulated electrons.