Arefi Hadi H, Corken Daniel, Tautz F Stefan, Maurer Reinhard J, Wagner Christian
Peter Grünberg Institute (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany.
Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, 52425 Jülich, Germany.
J Phys Chem C Nanomater Interfaces. 2022 Apr 21;126(15):6880-6891. doi: 10.1021/acs.jpcc.2c01514. Epub 2022 Apr 7.
Molecular nanofabrication with a scanning probe microscope (SPM) is a promising route toward the prototyping of metastable functional molecular structures and devices which do not form spontaneously. The aspect of mechanical stability is crucial for such structures, especially if they extend into the third dimension vertical to the surface. A prominent example is freestanding molecules fabricated on a metal which can function as field emitters or electric field sensors. Improving the stability of such molecular configurations is an optimization task involving many degrees of freedom and therefore best tackled by computational nanostructure design. Here, we use density functional theory to study 3,4,9,10-perylene-tetracarboxylic dianhydride (PTCDA) standing on the Ag(111) surface as well as on the tip of a scanning probe microscope. We cast our results into a simple set of design principles for such metastable structures, the validity of which we subsequently demonstrate in two computational case studies. Our work proves the capabilities of computational nanostructure design in the field of metastable molecular structures and offers the intuition needed to fabricate new devices without tedious trial and error.
利用扫描探针显微镜（SPM）进行分子纳米制造是通往非自发形成的亚稳态功能分子结构和器件原型制作的一条很有前景的途径。对于此类结构而言，机械稳定性方面至关重要，特别是当它们延伸到垂直于表面的第三维时。一个突出的例子是在金属上制造的独立分子，其可作为场发射器或电场传感器。提高此类分子构型的稳定性是一项涉及多个自由度的优化任务，因此最好通过计算纳米结构设计来解决。在此，我们使用密度泛函理论来研究站立在Ag(111)表面以及扫描探针显微镜尖端上的3,4,9,10-苝四羧酸二酐（PTCDA）。我们将研究结果转化为针对此类亚稳态结构的一组简单设计原则，随后我们在两个计算案例研究中证明了这些原则的有效性。我们的工作证明了计算纳米结构设计在亚稳态分子结构领域的能力，并为制造新器件提供了所需的直观认识，而无需进行繁琐的反复试验。
