Intermolecular Repulsion in Molecular Self-Assembly on Bulk Insulator Surfaces

体绝缘体表面分子自组装中的分子间排斥力

• 批准号: 391648454
• 负责人: Professorin Dr. Angelika Kühnle
• 金额: --
• 依托单位: University of Lincoln
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/391648454?language=en
• 关键词: Intermolecular; Repulsion; Molecular; Self; Assembly

In this project, we aim for exploring long-range repulsive interactions for controlling molecular self-assembly of organic molecules on bulk insulator surfaces. While short-range attractions are widely used to steer molecular structure formation on surfaces in a rational fashion, intermolecular repulsion has so far not been considered in a systematic way. Only few examples exist in literature demonstrating long-range intermolecular interaction in molecular self-assembly on surfaces. For most of these examples, interaction of electrical dipoles has been suggested as the origin of the repulsion. A systematic investigation of the general nature of this repulsion is, however, still lacking. From the prospective of steering structure formation, the rational use of intermolecular repulsion in molecular self-assembly bears the potential to enlarge the parameter space available for controlling the resulting structures´ shape and distribution on the surface.To develop strategies for making use of repulsive interactions in molecular structure formation on surfaces in a rational fashion, we will address three questions by performing scanning force microscopy measurements carried out in ultra-high vacuum at variable temperatures.First, we will investigate to what extend intermolecular repulsion is a general driving force in molecular self-assembly on surfaces. Clearly, even if a certain repulsion is present, experimental conditions might hamper the manifestation of the repulsion in the resulting molecular structures.Second, while repulsion of electrical dipoles appears as a very reasonable origin for intermolecular repulsion, the experimental confirmation for this assignment is still largely missing. To this end, temperature and coverage-dependent experiments are needed that shed light on the details of the interaction potential.Finally, we want to make use of the balance between short-range attraction and long-range repulsion for steering the resulting structures´ shape and distribution on the surface. To this end, we will systematically vary the involved interactions by changing functional groups at the molecule and by changing the substrate. Besides the interactions´ strengths and ranges, a key aspect here is to consider the effect of directionality, i.e., the spatial anisotropy of the involved interactions. We will compare our experimental results with Monte Carlo simulations to validate that a certain interaction characteristics will result in the experimentally observed structural motifs.Including intermolecular repulsion in the description of molecular self-assembly will allow for enhancing the structural variety that can be obtained in molecular structure formation on surfaces in a rational fashion.

在这个项目中，我们的目标是探索长程排斥相互作用控制有机分子在大块绝缘体表面的分子自组装。虽然短程吸引力被广泛用于以合理的方式引导表面上分子结构的形成，但分子间排斥力迄今尚未被系统地考虑。只有少数的例子存在于文献中，证明长程分子间相互作用的分子自组装表面上。对于这些例子中的大多数，电偶极子的相互作用被认为是排斥的起源。然而，对这种排斥的一般性质的系统研究仍然缺乏。从控制结构形成的角度看，合理利用分子间的排斥作用可以扩大控制表面结构形状和分布的参数空间，为了合理利用排斥作用形成表面结构，我们将通过在超高真空和不同温度下进行扫描力显微镜测量来解决三个问题。2首先，我们将研究分子间排斥力在多大程度上是表面上分子自组装的一般驱动力。很明显，即使存在一定的排斥力，实验条件也可能阻碍排斥力在所得分子结构中的表现。第二，虽然电偶极子的排斥力似乎是分子间排斥力的一个非常合理的起源，但这种分配的实验证实仍然很大程度上缺失。最后，我们希望利用短程吸引力和长程排斥力之间的平衡来控制所产生的结构在表面上的形状和分布。为此，我们将通过改变分子上的官能团和改变底物来系统地改变所涉及的相互作用。除了相互作用的强度和范围外，这里的一个关键方面是考虑方向性的影响，即，空间各向异性的相互作用。我们将我们的实验结果与Monte Carlo模拟进行比较，以验证一定的相互作用特性将导致实验观察到的结构motif.Including分子间排斥的分子自组装的描述将允许增强结构的多样性，可以在表面上的分子结构形成在一个合理的方式。

项目成果

Molecular Self-Assembly: Quantifying the Balance between Intermolecular Attraction and Repulsion from Distance and Length Distributions

• DOI: 10.1021/acs.jpcc.0c06676
• 发表时间: 2020-07
• 期刊: The Journal of Physical Chemistry C
• 作者: C. Schiel;Maximilian Vogtland;R. Bechstein;A. Kühnle;P. Maass

Molecular Stripe Patterns on Surfaces in the Presence of Long-Range Repulsive Electrostatic Interactions: Monte Carlo Simulations and Mean-Field Theory

存在长程排斥静电相互作用时表面上的分子条纹图案：蒙特卡罗模拟和平均场理论

• DOI: 10.1021/acs.jpcc.1c06305
• 发表时间: 2021
• 期刊: The Journal of Physical Chemistry C
• 作者: Christoph Schiel;Maximilian Vogtland;Ralf Bechstein;Angelika Kühnle;Philipp Maass
• 通讯作者: Philipp Maass

Kinetic control of molecular assembly on surfaces

• DOI: 10.1038/s42004-018-0069-0
• 发表时间: 2018-10
• 期刊: Communications Chemistry
• 影响因子: 5.9
• 作者: Chiara Paris;A. Floris;S. Aeschlimann;J. Neff;F. Kling;A. Kühnle;L. Kantorovich