Abstract The structure of self-assembled monolayers of 1,4-benzene dithiol (1,4-BDT) oligomers on Au(111) has been investigated using scanning tunneling microscopy (STM) measurements in ultrahigh vacuum combined with density function theory (DFT) calculations. The dominant adsorption geometry of 1,4-BDT oligomer chains involves an Au adatom linker forming a complex with two trans anchoring groups, resulting in a zigzag structure. STM measurements show preferential growth from step edges where gold adatoms can be extracted to form the oligomers. Ladder-like structures involving two parallel oligomer chains are observed at medium coverages, suggesting a stabilizing interaction between neighboring chains and reduced mobility following oligomerization. At high-coverages, the gold surface is covered with close-packed domains of oligomers. DFT STM simulations were performed using the Tersoff-Hamann method in order to elucidate structures observed in STM measurements.

中文翻译：

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nAu(111) 上 1,4-苯二硫醇的表面结构

摘要 在超高真空中使用扫描隧道显微镜 (STM) 测量结合密度函数理论 (DFT) 研究了 Au(111) 上 1,4-苯二硫醇 (1,4-BDT) 低聚物的自组装单层结构计算。1,4-BDT 低聚物链的主要吸附几何结构涉及 Au 吸附原子接头，与两个反式锚定基团形成复合物，从而形成锯齿形结构。STM 测量显示从台阶边缘优先生长，在那里可以提取金吸附原子以形成低聚物。在中等覆盖率下观察到涉及两条平行低聚物链的梯状结构，表明相邻链之间的稳定相互作用和低聚后流动性降低。在高覆盖率下，金表面覆盖着密堆积的低聚物域。