标题： 金(111)表面上的一维镍ocene片段链 显示英文标题

标题： One dimensional chains of nickelocene fragments on Au(111)

摘要： 我们研究了镍茂（NiCp$_2$）分子在单晶Au(111)基底上的温度依赖性沉积，揭示了不同的吸附行为和结构形成。 在低温（4.2 K）下，单独的 NiCp$_2$ 分子吸附在人字形拐角和台阶边缘，随着分子覆盖率的增加形成有序图案。 然而，在77 K时，分子分解，产生两种主要碎片：NiCp碎片，这些是被环戊二烯基（Cp）环覆盖的Ni原子，优先吸附在FCC空位上，以及表现出强基底相互作用的Cp自由基碎片。 NiCp碎片自组装成沿 $\langle 1 1 \bar{2} \rangle$ 方向的一维（1-D）链，在扫描隧道显微镜（STM）图像中显示更高的突出度。 Cp质子引起的应变和空间阻碍在链内诱导出手性图案，这由我们的密度泛函理论（DFT）模拟很好地再现。 相比之下，Cp碎片由于短程排斥力保持距离，并表现出低扩散势垒。 有趣的是，碎片是非磁性的，这通过STM测量和DFT计算得到确认，与完整Nc分子的磁信号形成对比。 除了线性链外，Ni-Cp碎片的二聚体沿 $\langle 1 \bar{1} 0\rangle$ 方向形成，需要金原子才能生成。 这些结果展示了通过表面合成构建复杂纳米结构的可行性，为通过选择保留碎片磁矩的基底实现低维磁系统提供了可能性。 显示英文摘要

摘要： We investigate the temperature-dependent deposition of nickelocene (NiCp$_2$) molecules on a single crystal Au(111) substrate, revealing distinct adsorption behaviors and structural formations. At low temperatures (4.2 K), individual NiCp$_2$ molecules adsorb on the herringbone elbows and step edges, forming ordered patterns as molecular coverage increases. However, at 77 K, the molecules dissociate, yielding two main fragments: NiCp fragments that are Ni atoms capped by cyclopentadienyl (Cp) rings, which preferentially adsorb at FCC hollow sites, and Cp radical fragments exhibiting strong substrate interactions. NiCp fragments self-assemble into one-dimensional (1-D) chains along the $\langle 1 1 \bar{2} \rangle$ directions, displaying higher protrusion in STM images. The strain and steric hindrance from the Cp protons induce chiral patterns within the chains, which are well-reproduced by our DFT simulations. In contrast, the Cp fragments maintain distances due to short-range repulsive forces and exhibit low diffusion barriers. Interestingly, the fragments are non-magnetic, as confirmed by both STM measurements and DFT calculations, in contrast to the magnetic signals from intact Nc molecules. In addition to linear chains, dimers of the Ni-Cp fragments form along the $\langle 1 \bar{1} 0\rangle$ directions, requiring gold adatoms for their creation. These results demonstrate the feasibility of constructing complex nanostructures based on metallocenes via on-surface synthesis, opening the possibility for realizing low-dimensional magnetic systems by selecting substrates that preserve the magnetic moment of the fragments.